Which of the following is most likely to be studied by direct observation?
a) the motion of the stars and planets in the universe.
b) the growth of crops in response to certain fertilizers.
c) global wind patterns.
d) the spreading of the ocean floor

Is this a single replacement reaction or there is no

The minerals found in bones are deposited by living cells called

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.