module 2 question 6

The cannon on a battleship can fire a shell a maximum distance of 48.0 km.
(a) Calculate the initial velocity of the shell.
m/s

(b) What maximum height does it reach? (At its highest, the shell is above a substantial part of the atmosphere--but air resistance is not really negligible as assumed to make this problem easier.)
m

(c) The ocean is not flat, since the earth is curved. How many meters lower will its surface be 48.0 km from the ship along a horizontal line parallel to the surface at the ship?
mDoes your answer imply that error introduced by the assumption of a flat earth in projectile motion is significant here? (Select all that apply.)
The error is significant compared to the distance of travel.
The error is insignificant compared to the distance of travel.
The error is insignificant compared to the size of a target.
The error could be significant compared to the size of a target.