Any one plz solve these numericals

Question 1 A body of mass m is attached to the spring which is elongated to 25cm by an applied force from its equilibrium position. (The spring constant is 0. 1 Nm-) a. Calculate the potential energy stored in the spring-mass system? b. What is the work done by the spring force in this elongation? Question 2 Compute the work done by the gravitational force for the following cases. Also justify your answer by giving appropriate reason for each case. D Path 3 4 Path 1 MACOR C Question 3 A spring of a spring gun is compressed a distance d from its relaxed state. A ball of mass m is put in the barrel. With what speed will the ball leave the barrel once the gun is fired. Question 4 Explain with the help of examples, how we can distinguish between open and closed system in thermodynamics