If the half-life of a radioactive group of atoms is 100 years, then how old is the rock if there have been two half-lives?

Astructure that is found in a plant cell and not in an animal cell is a ? central vacuole mitochondrion nucleus ribosome

(6.02 mc)what affect do marine protected areas have on environmental quality? they increase environmental quality by preventing resource overuse. they increase environmental quality by adding new species. they decrease environmental quality by removing all human activity. they decrease environmental quality by adding recycling facilities.

What is the best conclusion based on this data? the hypothesis was not supported because the data indicated that fertilizing plants does not improve plant growth. the hypothesis was supported; to get the best growth, use 5 milliliters of fertilizer per plant. the hypothesis was not supported; the data indicated that too much fertilizer can inhibit plant growth. the hypothesis was supported; to get the best growth, use 15 milliliters of fertilizer per plant.