Answer:
5. 43.98 (if not rounding pi, if rounding pi it is 43.96)
6. 201.06 (if not rounding pi, if rounding pi it is 200.96)
7. 72.8
8. 84
9. 3.6
10. 140
11. C
12. 12.6
Explanation:
5. C=2*pi*r
6. A=pi*r^2
7. angles in triangle must add up to 180
8. A=bh
9. radius is half of diameter
10. A=(hb)b/2
11. A=pi*r^2
12. radius is 1/2 of diameter