What is the answer to this question? Elastic potential energy stored in a spring with a spring constant of 16N/m is 247J. Calculate the extension?

Aheat engine that operates on a carnot cycle has an efficiency of 0.420 when its low-temperature reservoir is at 10 ∘c.part aby how many degrees celsius must you increase the temperature of the high-temperature reservoir to increase the efficiency to 0.600 if you continue to use the same low-temperature reservoir?