verbatimtex \magnification=\magstep1 etex

u=1cm;

beginfig(1);

z0 = (0,0);                        % z0  is point A

x10 = x0; y10 = y0 + u;            % z10  is point A
x11 = x10 + 2u;   y11 = y10;       % z11  is point C
x12 = x10 + 5.5u; y12 = y10;       % z12  is point B
x110 = x10; y110 = y10 + 0.15 u;   % z110 is top stroke    at A
z120 - z10 = z10 - z110;           % z120 is bottom stroke at A
x111 = x11; y111 = y11 + 0.15 u;   % z111 is top stroke    at C
z121 - z11 = z11 - z111;           % z121 is bottom stroke at C
x112 = x12; y112 = y12 + 0.15 u;   % z112 is top stroke    at E
z122 - z12 = z12 - z112;           % z122 is bottom stroke at E

draw z10--z12;
draw z110--z120;
draw z111--z121;

label.bot(btex ${\rm A}$ etex, z120);
label.bot(btex ${\rm C}$ etex, z121);
label.lrt(btex ${\rm B}$ etex, z122);

endfig;

beginfig(2);

z0 = (0,0);                             % z0  is origin

z110 = z0;                              % z110 is point B
x111 = x110 + u; y111 = y110;           % z111 is unlabelled
z112 = 2 [z110, z111];                  % z112 is unlabelled
z113 = 3 [z110, z111];                  % z113 is point R
z114 = 4 [z110, z111];                  % z114 is point C

x120 = x110; y120 = y110 + 4u;          % z120 is point A
x121 = x111; y121 = 0.90 [y110, y120];  % z121 is point O
x122 = x112; y122 = 0.70 [y110, y120];  % z122 is point P
x123 = x113; y123 = 0.40 [y110, y120];  % z123 is point Q

x130 = x110; y130 = y121;               % z130 is point K
x131 = x111; y131 = y122;               % z131 is point I
x132 = x112; y132 = y123;               % z132 is point H

x141 = x111; y141 = y120;
x142 = x112; y142 = y121;               % z142 is point E
x143 = x113; y143 = y122;               % z143 is point F
x144 = x114; y144 = y123;               % z144 is point G

z210 = 6 [z110, z111];                  % z210 is point M
x211 = x210 + 4u; y211 = y210;          % z210 is point N
x212 = 0.25 [x210, x211]; y212 = y210 + 4u; % z212 is point L

draw z110--z114;

draw z110--z120;
draw z111--z141;
draw z112--z142;
draw z113--z143;
draw z114--z144;

draw z120--z141;
draw z130--z142;
draw z131--z143;
draw z132--z144;

draw z120..z121..z122..z123..z114;

draw z210--z211--z212--cycle;

label.lft(btex ${\rm B}$ etex, z110);
label.bot(btex ${\rm R}$ etex, z113);
label.rt(btex ${\rm C}$ etex, z114);

label.lft(btex ${\rm A}$ etex, z120);
label.llft(btex ${\rm O}$ etex, z121);
label.llft(btex ${\rm P}$ etex, z122);
label.llft(btex ${\rm Q}$ etex, z123);

label.lft(btex ${\rm K}$ etex, z130);
label.lft(btex ${\rm I}$ etex, z131);
label.lft(btex ${\rm H}$ etex, z132);

label.rt(btex ${\rm E}$ etex, z142);
label.rt(btex ${\rm F}$ etex, z143);
label.rt(btex ${\rm G}$ etex, z144);

label.urt(btex ${\rm L}$ etex, z212);
label.bot(btex ${\rm M}$ etex, z210);
label.bot(btex ${\rm N}$ etex, z211);

endfig;

beginfig(3);

z0 = (0,0);                             % z0  is origin

z110 = z0;                              % z110 is point C
x111 = x110 + 1.0u; y111 = y110;        % z111 is unlabelled
z112 = 2 [z110, z111];                  % z112 is unlabelled
z113 = 3 [z110, z111];                  % z113 is point B

x120 = x110; y120 = y110 + 3u;          % z120 is point A
x121 = x111; y121 = 0.80 [y110, y120];  % z121 is unlabelled
x122 = x112; y122 = 0.50 [y110, y120];  % z122 is unlabelled

x130 = x110; y130 = y121;               % z130 is unlabelled
x131 = x111; y131 = y122;               % z131 is unlabelled

x141 = x111; y141 = y120;               % z141 is unlabelled
x142 = x112; y142 = y121;               % z142 is unlabelled
x143 = x113; y143 = y122;               % z143 is unlabelled

draw z110--z113;

draw z110--z120;
draw z111--z141;
draw z112--z142;
draw z113--z143;

draw z120--z141;
draw z130--z142;
draw z131--z143;

draw z120..z121..z122..z113;

label.ulft(btex ${\rm A}$ etex, z120);
label.bot(btex ${\rm C}$ etex, z110);
label.bot(btex ${\rm B}$ etex, z113);

x210 = x110 + 6u; y210 = y110;          % z210 is point O
x211 = x210 + 1.0u; y211 = y210;        % z211 is unlabelled
z212 = 2 [z210, z211];                  % z212 is unlabelled
z213 = 3 [z210, z211];                  % z213 is point N

x220 = x210; y220 = y210 + 4u;          % z220 is point M
x221 = x211; y221 = 0.80 [y210, y220];  % z221 is unlabelled
x222 = x212; y222 = 0.50 [y210, y220];  % z222 is unlabelled

x230 = x210; y230 = y221;               % z230 is unlabelled
x231 = x211; y231 = y222;               % z231 is unlabelled

x241 = x211; y241 = y220;               % z241 is unlabelled
x242 = x212; y242 = y221;               % z242 is unlabelled
x243 = x213; y243 = y222;               % z243 is unlabelled

draw z210--z213;

draw z210--z220;
draw z211--z241;
draw z212--z242;
draw z213--z243;

draw z220--z241;
draw z230--z242;
draw z231--z243;

draw z220..z221..z222..z213;

label.ulft(btex ${\rm M}$ etex, z220);
label.bot(btex ${\rm O}$ etex, z210);
label.bot(btex ${\rm N}$ etex, z213);

endfig;

beginfig(4);

z0 = (0,0);                        % z0  is point A

x10 = x0; y10 = y0 + u;            % z10  is point A
x11 = x10 + 2u;   y11 = y10;       % z11  is point B
x12 = x10 + 2.5u; y12 = y10;       % z12  is point E
x13 = x10 + 4.5u; y13 = y10;       % z13  is endpoint
x110 = x10; y110 = y10 + 0.15 u;   % z110 is top stroke    at A
z120 - z10 = z10 - z110;           % z120 is bottom stroke at A
x111 = x11; y111 = y11 + 0.15 u;   % z111 is top stroke    at B
z121 - z11 = z11 - z111;           % z121 is bottom stroke at B
x112 = x12; y112 = y12 + 0.15 u;   % z112 is top stroke    at E
z122 - z12 = z12 - z112;           % z122 is bottom stroke at E

z20 = z0;                          % z20  is point C
x21 = x20 + 3u;   y21 = y20;       % z21  is point D
x22 = x20 + 3.5u; y22 = y20;       % z22  is point F
x23 = x20 + 4.5u; y23 = y20;       % z23  endpoint
x210 = x20; y210 = y20 + 0.15 u;   % z210 is top stroke    at C
z220 - z20 = z20 - z210;           % z220 is bottom stroke at C
x211 = x21; y211 = y21 + 0.15 u;   % z211 is top stroke    at D
z221 - z21 = z21 - z211;           % z221 is bottom stroke at D
x212 = x22; y212 = y22 + 0.15 u;   % z212 is top stroke    at F
z222 - z22 = z22 - z212;           % z222 is bottom stroke at F

draw z10--z13;
draw z110--z120;
draw z111--z121;
draw z112--z122;

draw z20--z23;
draw z210--z220;
draw z211--z221;
draw z212--z222;

label.top(btex ${\rm A}$ etex, z110);
label.top(btex ${\rm B}$ etex, z111);
label.top(btex ${\rm E}$ etex, z112);

label.bot(btex ${\rm C}$ etex, z220);
label.bot(btex ${\rm D}$ etex, z221);
label.bot(btex ${\rm F}$ etex, z222);

endfig;

beginfig(5);

z0 = (0,0);                             % z0  is origin

z110 = z0;                              % z110 is point A
x111 = x110 + 1.5u; y111 = y110;        % z111 is point B
z112 = 2 [z110, z111];                  % z112 is point C
z113 = 3 [z110, z111];                  % z113 is point D
z114 = 4 [z110, z111];                  % z114 is point E

z119 = 1.3 [z110, z111];                % z119 is point F

x120 = x110; y120 = y110 + 6u;          % z120 is point a
x121 = x111; y121 = 0.90 [y110, y120];  % z121 is point b
x122 = x112; y122 = 0.70 [y110, y120];  % z122 is point c
x123 = x113; y123 = 0.40 [y110, y120];  % z123 is point d

x130 = x110; y130 = y121;               % z130 is point K
x131 = x111; y131 = y122;               % z131 is point L
x132 = x112; y132 = y123;               % z132 is point M

x141 = x111; y141 = y120;               % z141 is point l
x142 = x112; y142 = y121;               % z142 is point m
x143 = x113; y143 = y122;               % z143 is point n
x144 = x114; y144 = y123;               % z144 is point o

x149 = x119; y149 = y120;               % z149 is point f

draw z110--z114;

draw z110--z120;
draw z111--z141;
draw z112--z142;
draw z113--z143;
draw z114--z144;

draw z120--z149;
draw z130--z142;
draw z131--z143;
draw z132--z144;

draw z119--z149 dashed evenly;

draw z120..z121..z122..z123..z114;

label.bot(btex ${\rm A}$ etex, z110);
label.bot(btex ${\rm B}$ etex, z111);
label.bot(btex ${\rm C}$ etex, z112);
label.bot(btex ${\rm D}$ etex, z113);
label.bot(btex ${\rm E}$ etex, z114);

label.lft(btex $a$ etex, z120);
label.llft(btex $b$ etex, z121);
label.llft(btex $c$ etex, z122);
label.llft(btex $d$ etex, z123);

label.lft(btex ${\rm K}$ etex, z130);
label.lft(btex ${\rm L}$ etex, z131);
label.lft(btex ${\rm M}$ etex, z132);

label.top(btex $l$ etex, z141);
label.rt(btex $m$ etex, z142);
label.rt(btex $n$ etex, z143);
label.rt(btex $o$ etex, z144);

label.bot(btex ${\rm F}$ etex, z119);
label.top(btex $f$ etex, z149);

endfig;

bye;