As discussed in class, a perpetual motion machine of the second kind (that is, a device which could absorb heat from a single heat reservoir and delivers work, without any other permanent macroscopic change to the universe) would be quite useful, were it not for the inconvenient fact of it violating the second law: (a) search the internet in order to estimate the following: the average temperature of the earth's oceans, the amount (mass) of water in the oceans, the specific heat capacity of salt water, and the total annual energy used (chemical fuel, plus other electrical) by the human population, as of 2018. (b) if heat could be extracted from the oceans and converted entirely to work, estimate how many years of present human energy needs could be satisfied by lowering the temperature of the ocean by a single degree celsius