A plane is flying in a horizontal line describe the motion of the plane in this situation

The horizontal speed of a projectile is constant for the duration of its flight. This is because, once launched, there are no horizontal forces acting on the projectile (air resistance is usually ignored because it is very small) so horizontally the projectile will travel at a constant speed. For any calculations involving the projectile's horizontal motion, we use

distance=speed×time

d=vt

hi there!

out of the two, (b) precision would be more reasonable.   however, both a and b could be pretty reasonable.

-awesomerepublic   : )

i think the answer would be reserve.