Which graph shows the correct $$v$$ - $$x$$ graph of a freely falling body?

The displacement $$x$$ of a particle varies with time $$t$$, $$x=ae^{-pt}+be^{qt}$$, where a, b, p and q are positive constant. The velocity of the particle will

The angle of projection with the horizontal in terms of maximum height attained and horizontal range is given by

A body is projected vertically upwards. The times corresponding to height $$h$$, while ascending and while descending are $$t_1$$ and $$t _2$$ , respectively. Then, the velocity of projection is ($$g$$ is acceleration due to gravity)