Motion in a Plane Questions

For a projectile projected at angles $(45^{\circ }-\theta )$ and $(45^{\circ }+\theta )$, the horizontal ranges described by the projectile are in the ratio of:

A car turns at a constant speed on a circular track of radius $100\text{m}$, taking $62.8\text{s}$ for every circular lap. The average velocity and average speed for each circular lap respectively is :

The vectors $\vec{a}$ and $\vec{b}$ are such that:$|\vec{a}+\vec{b}|=|\vec{a}-\vec{b}|$ The angle between the two vectors is :