A) 1 1 1 23 3 3 20S S  S  S  S  CM ADH CBF ACD ABC ABCDB)...

5. a) 1 1 1

²

3 3 3 20S S  S  S  S  cm

ADH

CBF

ACD

ABC

ABCD

b) S

EFGH

= S

AFCH

- (S

AHF

+ S

CGF

) = 1 1S  S  S 

A FCH

AHF

CFH

2 21 1   S S S

A FCH

A FCH

AFCH

    2S

^ABCD

3S

^ABCD

  1

2

20( )3S

^ABCD

cm