Hello help me please The following parametric equations are :

x(t) = 2cosπt
y(t) = 2sinπt
z(t) = 0
Determine:

1) the modulus of the velocity vector at the instant t.
2) the modulus of the acceleration vector at any time "t'
3) The equation of the mobile and its trajectory.

Balloon a has charge q, and identical mass balloon b has charge 10q. you hang them from threads near each other. choose all of the statements with which you agree. check all that apply. a. a and b exert the same magnitude forces on each other. b. the force that a exerts on b is 10 times the force that b exerts on a. c. the angle between the thread supporting a and the vertical is < the angle between the thread supporting b and the vertical. d. the force that a exerts on b is 1/10 the force that b exerts on a.