How do I answer this

Use the following information to answer the next question. Conventional Power Plant 35% Electrical power Fuel in 100% Conventional power plant Waste 65% heat Numerical Response 1 The efficiency of the conventional power plant is %. (Record your answer to two digits in the numerical-response section on the answer sheet.) 1. Some forms of cancer can be treated by exposure of the affected tissues to cobalt-60, a radioactive isotope. In the equation for the production of this isotope, 27 Co + x -> 27Co x represents A. a proton B. a neutron C. an electron D. an alpha particle