Average Acceleration and Instantaneous Acceleration

The velocity-time plot for a particle moving in a straight line is shown in the figure.

Which of the following statement(s) is/are correct?

The velocity of a particle is zero at $t=0$. Which of the following statement(s) is/are correct?

Mark the correct statements, for a particle moving in a straight line.

An object may have

A particle moves along the $x$-axis as $x=u(t- 2)+a(t- 2{)}^2$. Which of the following is correct?

An athlete takes $2.0 \mathrm{s}$ to reach his maximum speed of $18.0 \mathrm{km} {\mathrm{h}}^{-1}$. What is the magnitude of his average acceleration?

The increase in the speed of a car is proportional to the additional petrol put into the engine. Is it possible to accelerate a car without putting more petrol or less petrol into the engine?

Two particles $A$ and $B$ start from rest and move for equal time on a straight line. The particle $A$ has acceleration $a$ for the first half of the total time and $2a$ for the second half. The particle$B$ has acceleration $2a$ for the first and $a$ for the second half. Which particle has covered a larger distance?

If a particle is accelerating, it is either speeding up or speeding down. Do you agree with this statement?