Answer:
4.870 cm (correct me if i'm wrong i'm just a human)
Step-by-step explanation:
formula for a cone: 1/3 x (pi—sorry cuz i dont have a pi symbol in my keyboard ha) x r² x h
pi= 22/7 @ 3.142...
r²= radius ^2
h = height
1/3 x (22/7) x 7² x h = 250 cm3
h = 250/ (1/3 x 22/7 x 7²)
=4.870 cm