Groundwater to replenish our freshwater lakes and rivers. in two or more complete sentences, describe a source of contaminate and predict the effects that contaminate would have on earths ecology.

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

The diagram below shows a cell placed in a solution. a cell is shown placed inside a beaker. it is labeled cell. the solution inside the beaker is labeled 40% salt solution and the solution inside the cell is labeled 20% salt solution. only water is allowed to move in and out of the cell. what will most likely happen to the cell? it will expand as water moves out of it. it will shrink as water moves out of it. it will expand as water moves into it. it will shrink as water moves into it.

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false