True or false? This is about Newton's laws of Motion

Which describes an object in projectile motion? check all that apply.a.gravity acts to pull the object downb.the object moves in a straight path.c.the forward velocity of the object is 0 m/s.d.the object’s inertia carries it forward.e.the path of the object is curved.

Ajoint produces movement when its angle decreases. which type of movement is it?

How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 4.57×10−21 newtons?