E 1
1 point
Which of the following is an elemental substance?
Select all the correct answers.
Mercury
2
Oxygen (O2)
3
Platinum
Chlorine (C12)
Carbon Dioxide (CO2)

Which object forms when a supergiant runs out of fuel? a red giant a black hole a white dwarf a neutron star

Explain why scientists use shared characteristics to make cladograms.

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.