Which of the following statements is true? give all correct answers

a) if the acceleration of a body is constant in a given inertial reference frame (a frame of reference with constant velocity), it is constant in all other inertial reference frames.
b) in projectile motion when air resistance is negligible it is never necessary to consider 3d motion rather than 2d motion.
c) if the elevation angle of a projectile at launch increases, its range decreases.
d) it is possible to be accelerating if you are traveling at a constant speed.
e) you are driving a distance directly behind a pickup truck, going at the same speed as the truck. a crate falls from the bed of the truck to the road. your car will hit the crate before the crate hits the road if you neither brake nor swerve.
f) if the elevation angle of a projectile at launch increases, its time-of-flight until impact also increases.