Juliet started working with a radioactive substance. In 1997, she started with 200 g. When she measured again in 2002, she had 100 g left. In 2007, she had 50 g. Which substance is she most likely measuring?

rubidium-91
iodine-131
cobalt-60
carbon-14

Which of the following statements about pesticides and residue is false? a. most conventionally grown produce has detectable levels of pesticides when purchased from the store. b. the us government has determined that small levels of pesticides in produce is safe for humanconsumption. c. organic produce always will be pesticide-free. d. farm workers, children, and pregnant women are at greatest health risk from pesticides. select the best answer from the choices provided.

If a volcano’s magma is high in silica, the volcano will probably a. erupt quietly. b. remain dormant. c. erupt explosively. d. produce dark-colored lava.

The earth is actually quite a dry planet true or false