An object has a position given by vec$(r)=[2\mathrm{.}0m+(10\mathrm{.}0\frac{m}{s})t]hat(i)+[8\mathrm{.}0(m)-(3\mathrm{.}80\frac{m}{s^2})t^2]hat(i),$ where quantities are in SI units.

a$)$ What is the velocity of the object as a function for time?

b$)$ What is the acceleration of the object as a function for time?

c$)$ What is the speed of the object at time $t=2\mathrm{.}00s?$

d$)$ What is the average velocity between $t=1\mathrm{.}00s$ and $t=3\mathrm{.}00s?$