f1 maths

19.
因為佢個底係正五邊形(regular pentagon)，所以每條邊都係6cm，所以l=6

a.The total surface area of the container is:
(6)(10)(5)=300cm2(2字上標)(cm square)
b. The volume is:
(6)(1.72)(10)=103.2cm3(3字上標)(cm cube)
c.
volume=103.2cm cube
你係個心入面將容器分開一半，一半滿左另外一半大約有五分之三滿左
(103.2)(8/10)=82.56
nearest 10 cm cube=
80cm cube

2010-08-17 17:29:42 補充：
b.
佢話五邊形面積=邊長*1.72