Space probes have shown that there are mountains, dry river-valleys and volcanoes on Mars. Scientists believe Mars, like Earth, has all three types of rock: igneous, metamorphic and sedimentary. Using the information above, explain why.

Drive down any three characteristic of modern periodic table

Which atom or ion is the largest? a. k b. k+ c. ca d. ca2+ e. li

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.