Let's say the original radius was "r", so the circumference is 2πr and the area is πr².
Now when you double the radius, the you get a new circle with radius 2r, circumference 2π(2r) = 4πr, and area π(2r)² = 4πr².
If the formula is V= Ab x H
then the base and height is 4 and 7.5 because it doesn’t need to be the bottom so you multiply 7.5 x 4= 30 but we have to half it since it’s a triangle which is 15 and then multiply 10 which gives us 150 cm squared.
I got 10 I'm not sure if this or correct or not but I'm not sure somebody else probably has a better answer
PART A
rectangle : circle
5:13
PART B
5x3 : 13x3
15 : 39
Hope this helped! :)
