what is the area for #2 and #4
evidence is would be greatly appreciated!

Answer:
2.)70
4.)451,17
Step-by-step explanation:
2.)
a1 = 8*5 = 40
a2 = ((20-8)*5)/2 = 30
aTotal = 40+30 = 70
4.)
a1 = 18*18 = 324
a2 = (πr²)/2 = 127,17
aTotal = 127,17 + 324 = 451,17