Who organized elements into four groups based on properties:

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.

How do you lengthen a pattern piece? (family and consumer science, sewing)

Find the number of grams of hcl needed to react completely with .50 moles of magnesium.