Answer:
22.2m
Explanation:
vol of a sphere = 4/3 x pi x r^3
vol of a hemisphere is 1/2 the vol of a sphere, so vol of a hemisphere= 2/3 x pi x r^3
2/3pi x r^3 = 257
Divide both sides by 2/3pi
r^3 = 122.708
Cube root both sides.
r = 11.077
Diameter is twice the radius, so diameter = 22.154m
To the nearest 10th of a meter this is 22.2m.
Hope I helped x