VCAA 2007 EXAM 1

[mooimachicken]

Hi was just wondering if someone could go through how VCAA gets answer D with this question? Thanks

[studynotes]

we know area of hemisphere is 1/2 *4pi*r^2= 2pi*(20)^= 2513
then the side surface of cylinder pi*d*h=pi*40*30=3769
then the bottom so the circular base pi*r^2=pi*(20)^2=1256

then add them all together 2513+3769+1256= 7538

which is closest to D 7540