A spring has a constant of k=7.50 n/m. if the spring is displaced 0.550m from its equilibrium position, what is the force that the spring exerts? assume for this and for all other questions in the pre-laboratory that g=9.8m/s^2. show your work

Two kilograms of air within a piston–cylinder assembly executes a carnot power cycle with maximum and minimum temperatures of 800 k and 300 k, respectively. the heat transfer to the air during the isothermal expansion is 60 kj. at the end of the isothermal expansion the volume is 0.4 m3. assume the ideal gas model for the air. determine the thermal efficiency, the volume at the beginning of the isothermal expansion, in m3, and the work during the adiabatic expansion, in kj.