An isotope has a half-life of 5.0 days. What percent of the original material will be left after 10.0 days?
15.0 days?
22 days?

Ineed with these last two questions: 1) what are two types of cold air masses that influence the weather in north america? name them and describe their humidity. 2) describe the motion of a cold air mass and a warm air mass and the weather you would expect at a warm front and an occluded front.

Light traveling in a medium with a refractive index 1.19 is incident on a plate of another medium with index of refraction 1.79. at what angle of incidence is the reflected light fully polarized?

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?