The speed of a wave in a medium is effected by_,_, and_

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.

What are atoms of the same element with varying number of neutrons

Why should seat belts not be mandatory quick plz