%PDF-1.7 % 12 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 13 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /Annots [ 8 0 R ] /PZ 1 >> endobj 13 0 obj <> stream xXOk@z'O輻};2c..uBi6R\Kk=%1M; KdL6oͼp1ݣ2ٴ0|-A1lل wE>ܛ}Jf4*p ?X N)]4k=  V': ,K `WB۲:!{;vӖC5դ3&\E%☥y&q YG2^6ްdt>cϮL\4! S_sMtMT_4IhқO{7zS/L%ܩ| < Vn.rՏ?6ؒ(r{c!AE.TCB8]"Bh`<.d ;`)+!ͳ5E39H6j Pd0Ƿb[•Cza03]4Ek&k4ӹ} nqjvQ&>ҽL$3Дd{:Bwsբׅ֟!~ Xt9} endstream endobj 14 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 15 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 15 0 obj <> stream x335W(W0P,X `g``B%ҹBL,B\C Ph TC!\YNds3S=cSS\.S|@ a9  ڦ`dbgaf @dz&xuB,RE @AU1BHBFw񡚱 !^ U')!׏E44 2$"̌, A``ƺPY\n_Ow'?8p ~| ^sSPR+P68Z"R0P!LMPPA9Ք,lD#,QSjE >UT^JISsO 1}VS=}Thp8Ġ%JZAOJ )p) cQe!?C`*eCهFe 'b4s ;h1JDΔSu5mug9C=sZbϜ./ LqH{ea?CY3!]ߏoW/}-C$)7"N90\^(rj#=s3(7G!DI23C=S]zƆ(S )p@0$ endstream endobj 16 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 17 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 17 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) a <BMSѫ xd@f[N&:|ZB2 'O53G׏ |:g! q(hEP%P<`|H-ȧCڏHe_z<hT0(P'$؄V`01G.z`#C˸䈯;|*!]x}D3Z cbh V}ݰs(cK5u /%1RbB !GRϏ=;A6j瑡G#s-~A:lǣR 7-|1&&HP%J1;HHE.b MQذ\;|'YCCO7/5X )! IASnDr;`JLL,@ l陛A9 $MZ h14c}`fE> /PZ 1 >> endobj 19 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) :~S<B:|*G4OS3V! d.k[Co v?|#X,h֡93s$0,cW<}e+NƘ܎^KǂOu JCً/6``ȆMC=L)ʓ蟠ҥ%0!3!] 姉9j )ȗC=~C=+[g`ow!AL`.8/102Xƕ`˕Cڷ"8Zb4K lid=[xoא&Z3ٛo{u8(&3 3hE#jAGxi;# bPOH a@@0h$q(LqA)2135R0q. mgn(h4ijQ]zxU LY)@Eك endstream endobj 20 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 21 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 21 0 obj <> stream x335W(W0P,X `g``B%ҹBL ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPŅE @DL@NV07535TIQ֨zQ'nçxCѶ !^ s!6Bs4(b V).b%0+bLLhfSVPX!Ԑ9³~ ТHɏ=~יa0=ijINF4y$KqFK%jQ˛~֝V1((Pϭ5XJeYYZԧƨ7[1RҾ'$^7njQʰ۠星n_H;vB#)f)6,aFh0 OUqݛQ7=dQeΡ0tO {PKo@n1wG!fǥ~AL@/ S4C@8 ܈8 wr)Y1v737rsI43F.=ch) y F endstream endobj 22 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 23 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 23 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) ~  F  Pe\n_Ow'?) w/ԌU) b={ CfHu,3ђoHj?Φ&d_NeK` ?cԒ=!ihSSs4V|A~9WFqLVGz a~9ؒ ;$w1iaq?s!J==}ϰ)P̀10l؃ZSAA>62'e {3ꆴQs;6?bzꆖdƁ- 5j$JQ0 h\`%ACLL(%-"  dX 0F)HH1>LѤ 3`2eg M x>@yj7:Y  endstream endobj 24 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 25 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 25 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) :~ MM F  Pe\ ';CHCLL\TAl4cB@F,X|: 7Dxޏh'XOFЊCڳh tςpr:xw@4 S4C@8 ܈8 wr)YB2c037rsI43.=ch) ܍yf8A1 endstream endobj 26 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 27 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 27 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) ~ N !I11q>~R +`|#hEow~X/ a:  g  óSBRS̑bw h.K1 C_W451(| =OOM- _>J[`3}\>`[ iu({ !(h~D-u8K_ؤ$ ROiļCڗxJ/@*kɾ21rW̑jmBSU[qրA -qղ$ȓu[Tq@~LZO?aeafHGpR.#=S## P[FzfPnB0Fifeg 4BAW"c$Mb endstream endobj 28 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 29 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 29 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !)  !^ y1.ĩ JQ0 `cz````W!O_gMLC[0#6$(tN:f(a 3P8> -~c0`D_KoȓCكHA`RCRlj#YCHWmT՝oQ3A*d/`ϐR?]ICƖ(Dz%J'MqqLVӎ-u!"*j=M JCޟxZ69~t(O&?&&> /PZ 1 >> endobj 31 0 obj <> stream xݘOALJ P/ngf;K`!kC҅% $r޸p3;HH'o]m-Qmv}3f>n x>"~u)Ƶ\†S # Ol^nd-/\OX^w ;OydL>{Sq|;ׯL:lK_n-v[﬎DU D\С a)tȱP\J~0!=CԞIc^J}ALWдNOtQm% oF+_SMfѪ P!Ez Z/O<&gS3rM#L87"s3*4Bc ,BХV> /PZ 1 >> endobj 33 0 obj <> stream xݘOKA'E BMr Ձ`b*"XZ~~^ziڏ۝͟f6a7wgߙy7̇$V_mq, M"d& MnztG|ce |˰ndbp& qՐgfͭ^ZD ~Yl6w7Q Xė`AĒJ$vw;LnKPd`'6z뇿ĵW%aqV(xV#sR6S!gj8,v;b!x}r-~|y=\Zmrң#k7h&Ni0M!)zk/5^wmfK,koS%,koz ]͛F/!]^ Zu$Q7ٚqM-ڌ-*+[9}/ᐩ+' '¶ Vx;M endstream endobj 34 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 35 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 35 0 obj <> stream xݘAKA'='(=`&5TQF]HAAihqBAQ1xHRA'O^ ~pFwlLMc6y3f~vX38?̬,1ơhj2%~1WÝ=2+Fɣ9Um1` <-eV.nV:4ժ  ;6J) 6#:#.()DFY(:+܋J~tzܢ$)0yggڿwgGd-żT$#z&P)"F)ڜ. h:IuFfe> /PZ 1 >> endobj 37 0 obj <> stream xݗJ@Ǜ> /PZ 1 >> endobj 39 0 obj <> stream xݗJ1ǻi.dgÖnsJOEۋx<(x 7YL݊UQ,N&3gn8#l7̭ qGh[06F{P!ώw#w8ӵ$va|"t2-0MD+ikA2BM$YdC%Hr̫Nr<{&R?Хz]HG,IoW/$GP%taѥ]Hхtp]}b;',]|cFQ 6?x)COWؔL5 o tW endstream endobj 40 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 41 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 41 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) ~U:%OЌUFX<1 2DAZ>!&R D9"u01.eW!O*ijKoZ>R cfp~ MM ThP'HݏG˸L?L7!%I`H, "C=BMPJ5l2A}wq0|P%Yv"(F3K1{w{2A!JĖ+ӭ?Qsr?)`>3F͋uǂ­ -Qij; !/a!)2bLLhYKUUYmΡ Q؊e؟@@xrxYd0F)HHLѤE0ʀvC#N04UQȣ ? endstream endobj 42 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 43 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 43 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) ~  N !>~Ra3MԌUfX<3 3D_ct硺~C_fH4`c 9eWm~RC_H5ŀoy-C_HG`cRC~H!/r%Mu2A*7u451( ?1ӭ' i/4D=ΐѠ CڏuzD_ܯuCڗH%|BMk( #*ѯBYfq%~aa $JS%WembBAQ{\cbBAy$HLZ~"P>=ȓ9uZ3t6iߙ DED[ >-8{@@hr0YR0F)HHvLѤŗ0vCK04SLȣ^ endstream endobj 44 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 45 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 45 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !) :~=MM N !~RIG̢gMӌU+ b؀W?ưRȒc'|1&&H|18 A %o_ߠCg6` ~?%]݀wH HUTO~E+R@~P ZԐ|!/%*>,=e'~lH ,bآ:!`POHF`c=_FemO7&T& VT ipFGhYw6N}7cP!R`hXo_y1:C{H {!%le-X 2[6}T0C|W1w Kh; mJh$qLqA)2135R0].kgn(h4ie(]zR 9)17 endstream endobj 46 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 47 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> endobj 47 0 obj <> stream x335W(W0P,X `g``B%ҹB݌ ̀ !i !\MP@``hP4@4İYTT!9K?"T%+qXNqPE(]h0"4 榆z !)  &V~n*h IJՌUiy jX|3 4D)ăZz]&^LO8}gf_nL ?TŘ$!Cc34`btZY ܋C{H32`Uu:%gw [!;y>~i|e-4ZmH Xa_gCw&gzKܯH5C*Wu451(1[L<[3zQ9h6CٗHŋD_YK!GS:T|VUsH 4`D^|!0a~+h~!7V|BMk( CKB6я';C- 4īBrSISz]uHFlPP(8HҎ)JpP#(O@m?aeafHGpR.#=S## PFzfPnB0Fifeg 4|BA"!TjD endstream endobj 48 0 obj << /Type /Page /Parent 1 0 R /LastModified (D:20250806100055+08'00') /Resources 2 0 R /MediaBox [0.00 0.00 595.28 841.89] /CropBox [0.00 0.00 595.28 841.89] /BleedBox [0.00 0.00 595.28 841.89] /TrimBox [0.00 0.00 595.28 841.89] /ArtBox [0.00 0.00 595.28 841.89] /Contents 49 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /Annots [ 9 0 R 10 0 R 11 0 R ] /PZ 1 >> endobj 49 0 obj <> stream xVo@dcVg;KڊU-*H$qRJCZdUH-r(΄X3Y n>lP;)ݽｳ3`-53yjL҂FcIIij=`@C'b$fR؊Ja]2hNidL˧?~ƔBrLXAuQ)+XGwWfj'+}jd_0cˆ|y0?(m'zϽimQ-$[^UҰ~vSTWԽ%yNB]G`]7L,__~O0+,(N:؆.skӯIhrL|ˣ> endobj 3 0 obj <> endobj 4 0 obj <> endobj 50 0 obj <> /FontDescriptor 51 0 R /DW 1000 /W [ 1 [ 207 270 342 467 462 797 710 239 374 374 423 605 238 375 238 334 ] 17 26 462 27 28 238 29 31 605 32 [ 344 748 684 560 695 739 563 511 729 793 318 312 666 526 896 758 772 544 772 628 465 607 753 711 972 647 620 607 374 333 374 606 500 239 417 503 427 529 415 264 444 518 241 230 495 228 793 527 524 524 504 338 336 277 517 450 652 466 452 407 370 258 370 605 ] ] >> endobj 51 0 obj <> endobj 6 0 obj <> endobj 7 0 obj <> endobj 52 0 obj <> /FontDescriptor 53 0 R /DW 1000 /W [ 1 [ 207 270 342 467 462 797 710 239 374 374 423 605 238 375 238 334 ] 17 26 462 27 28 238 29 31 605 32 [ 344 748 684 560 695 739 563 511 729 793 318 312 666 526 896 758 772 544 772 628 465 607 753 711 972 647 620 607 374 333 374 606 500 239 417 503 427 529 415 264 444 518 241 230 495 228 793 527 524 524 504 338 336 277 517 450 652 466 452 407 370 258 370 605 ] ] >> endobj 53 0 obj <> endobj 5 0 obj << /Type /XObject /Subtype /Form /FormType 1 /Filter /FlateDecode /BBox [0.00 0.00 595.28 76.54] /Matrix [1 0 0 1 0 0] /Resources << /ProcSet [/PDF /Text /ImageB /ImageC /ImageI] /Font << /F3 6 0 R /F1 3 0 R >> >> /Length 154 >> stream x0 D|ō'!iJR7 [-]}lDCΑ{>Č|A S]Q+CQG5:>GD#lNWGbwzb5{G{r BpTw{OiH endstream endobj 2 0 obj << /ProcSet [/PDF /Text /ImageB /ImageC /ImageI] /Font << /F1 3 0 R /F2 4 0 R /F3 6 0 R /F4 7 0 R >> /XObject << /XT5 5 0 R >> >> endobj 8 0 obj <> /H /I>> endobj 9 0 obj <> /H /I>> endobj 10 0 obj <> /H /I>> endobj 11 0 obj <> /H /I>> endobj 54 0 obj << /Title (2020-2026^tN-VIGBTLN^W:RgNLNgbTJ) /Author () /Subject (2020-2026^tN-VIGBTLN^W:RgNLNgbTJ) /Keywords (2020-2026^tN-VIGBTLN^W:RgNLNgbTJ TCPDF) /Creator (TCPDF) /Producer (TCPDF 5.9.133 \(http://www.tcpdf.org\)) /CreationDate (D:20250806100055+08'00') /ModDate (D:20250806100055+08'00') /Trapped /False >> endobj 55 0 obj << /Type /Metadata /Subtype /XML /Length 4494 >> stream application/pdf 2020-2026年中国IGBT行业市场分析与行业调查报告 йго 2020-2026年中国IGBT行业市场分析与行业调查报告 2020-2026年中国IGBT行业市场分析与行业调查报告 2025-08-06T10:00:55+08:00 TCPDF 2025-08-06T10:00:55+08:00 2025-08-06T10:00:55+08:00 2020-2026年中国IGBT行业市场分析与行业调查报告 TCPDF TCPDF 5.9.133 (http://www.tcpdf.org) uuid:70a66944-921e-4ebe-f08d-245f1f817d56 uuid:70a66944-921e-4ebe-f08d-245f1f817d56 http://ns.adobe.com/pdf/1.3/ pdf Adobe PDF Schema http://ns.adobe.com/xap/1.0/mm/ xmpMM XMP Media Management Schema internal UUID based identifier for specific incarnation of a document InstanceID URI http://www.aiim.org/pdfa/ns/id/ pdfaid PDF/A ID Schema internal Part of PDF/A standard part Integer internal Amendment of PDF/A standard amd Text internal Conformance level of PDF/A standard conformance Text endstream endobj 56 0 obj << /Type /Catalog /Version /1.7 /Pages 1 0 R /Names << >> /ViewerPreferences << /Direction /L2R >> /PageLayout /SinglePage /PageMode /UseNone /OpenAction [12 0 R /FitH null] /Metadata 55 0 R >> endobj xref 0 57 0000000000 65535 f 0000019380 00000 n 0000021998 00000 n 0000019567 00000 n 0000019673 00000 n 0000021582 00000 n 0000020562 00000 n 0000020673 00000 n 0000022143 00000 n 0000022424 00000 n 0000022705 00000 n 0000023041 00000 n 0000000015 00000 n 0000000405 00000 n 0000001047 00000 n 0000001419 00000 n 0000002116 00000 n 0000002488 00000 n 0000003175 00000 n 0000003547 00000 n 0000004200 00000 n 0000004572 00000 n 0000005247 00000 n 0000005619 00000 n 0000006275 00000 n 0000006647 00000 n 0000007293 00000 n 0000007665 00000 n 0000008294 00000 n 0000008666 00000 n 0000009311 00000 n 0000009683 00000 n 0000010348 00000 n 0000010720 00000 n 0000011367 00000 n 0000011739 00000 n 0000012377 00000 n 0000012749 00000 n 0000013224 00000 n 0000013596 00000 n 0000014063 00000 n 0000014435 00000 n 0000015083 00000 n 0000015455 00000 n 0000016158 00000 n 0000016530 00000 n 0000017202 00000 n 0000017574 00000 n 0000018307 00000 n 0000018711 00000 n 0000019826 00000 n 0000020383 00000 n 0000020831 00000 n 0000021393 00000 n 0000023298 00000 n 0000023784 00000 n 0000028361 00000 n trailer << /Size 57 /Root 56 0 R /Info 54 0 R /ID [ <70a66944921e4ebef08d245f1f817d56> <70a66944921e4ebef08d245f1f817d56> ] >> startxref 28571 %%EOF