The energy yield of a nuclear weapon is often defined in terms of the equivalent mass of a conventional explosive. 1 ton of a conventional explosive releases 4.2 gj. a typical nuclear warhead releases 250,000 times more, so the yield is expressed as 250 kilotons. that is a staggering explosion, but the asteroid impact that wiped out the dinosaurs was significantly greater. assume that the asteroid was a sphere 10 km in diameter, with a density of 2500 kg/m3 and moving at 30 km/s. part a: what energy was released at impact, in joules? assume all kinetic energy of the asteroid to be released. part b: what energy was released at impact, in kilotons? assume all kinetic energy of the asteroid to be released.