How much heat, in joules, must be added to a 29.9 g iron block with a specific heat of 0.449 J/g °C to increase its temperature from 17.7 °C to 579 °C?

Americium-241 undergoes fission to produce three neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 1.8 neutrons per fission event, which will be effective at achieving a critical mass? check all that apply. remove a deflective shield surrounding the sample. remove absorbent material mixed in with the sample. compress the sample of americium-241.