What is the work done by a spring force in a cyclic process?

$A$ spring with a spring constant of $5 \times 10^3 \ N/m$ is initially in its natural state. It is stretched by $5 \ cm$. How much work is required to stretch it by another $5 \ cm$?

$A$ spring has a natural length $l$ with one end fixed to the ceiling. The other end is fitted with a smooth ring which can slide on a horizontal rod fixed at distance $l$ below the ceiling. Initially, the spring makes an angle of $60^{\circ}$ with the vertical, when the system is released from rest. Find the angle of the spring with the vertical, when the velocity of the ring reaches half of the maximum velocity, which the ring can attain during the motion.

$A$ block of mass $m$ moving with speed $v$ compresses a spring through distance $x$ before its speed is halved. What is the value of the spring constant $k$?

$A$ block of mass $M$ moving on a frictionless horizontal surface collides with a spring of spring constant $K$ and compresses it by a length $L$. The maximum momentum of the block during the collision process is

Work done on a certain spring when it is stretched to $1 \text{ mm}$ from its mean position is $10 \text{ J}$. The amount of work that must be done on the spring to stretch it further by $1 \text{ mm}$ is: (in $\text{ J}$)