What is the nature of the displacement-time graph of a body moving with constant acceleration?

The area under the velocity$-$time graph gives the value of

Define velocity.

$A$ car travels $100\, km$ east and then $100\, km$ south. Finally,it comes back to the starting point by the south-east route. Throughout the journey the speed is constant at $60\, km\, h^{-1}$. The average velocity for the whole journey if the time taken is $3.3\, h$ is

$A$ frog hops along a straight line path from point $A$ to point $B$ in $10 \, s$ and then turns and hops to point $C$ in another $5 \, s$. Based on the provided number line,calculate the average speed and average velocity of the frog for the motion between: $(a)$ $A$ to $B$ $(b)$ $A$ to $C$ (through $B$).

$A$ moving body is covering a distance directly proportional to the square of time. The acceleration of the body is