Which of the diagrams shown in figure most closely shows the variation in kinetic energy of the earth as it moves once around the sun in its elliptical orbit?

Explain with reason, whether the shown curve can be a possible trajectory traced by a projectile (neglect air friction).

A man, of mass $m$, standing at the bottom of the staircase, of height $L$ climbs it and stands at its top.

A bullet of mass $m$ fired at $30°$ to the horizontal leaves the barrel of the gun with a velocity $v .$ The bullet hits a soft target at a height $h$ above the ground while it is moving downward and emerges out with half the kinetic energy it had before hitting the target. Which of the following statements are correct in respect of bullet after it emerges out of the target?

Two blocks $M_1$ and $M_2$ having equal mass are free to move on a horizontal frictionless surface. $M_2$ is attached to a massless spring as shown in Figure. Initially ${\mathrm{M}}_2$ is at rest and ${\mathrm{M}}_1$ is moving towards $M_2$ with speed $v$ and collides head-on with $M_2$.Which of the following is true ?