Answer:
7. 2355 m
8. 1570 km
9. 157 cm
10. 40.82 m
Explanation:
The circumference of a circle is pi * diameter or 2 * pi * radius.
If you are given the diameter, just multiply it by pi, 3.14.
If you are given the radius, then multiply the radius by 2 and then by pi, 3.14.
7. d = 750 m
circumference = pi * d = 3.14 * 750 m = 2355 m
8. d = 500 km
circumference = pi * d = 3.14 * 500 km = 1570 km
9. r = 25 cm
circumference = 2(pi)r = 2 * 3.14 * 25 cm = 157 cm
10. r = 6.5 m
circumference = 2(pi)r = 2 * 3.14 * 6.5 m = 40.82 m