Which scientist observed that compounds are always joined together in fixed ratios? a. boyle b. bohr c. lavoisier d. proust

Modern weaponry has increased the number of deaths in wars and violent conflicts.

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.

Which of the following units is not an official si unit? mole liter kilogram ampere