The half-life of Po-218 is three minutes. How much of a 2.0 gram sample remains after 15 minutes?

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

What conclusion can be made based on the temperature of soil when the light hits the soil at 0°, 45°, and 90° angles in section 2 of the experiment? did your results support your hypothesis? why or why not?

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal responds by in order to its core temperature?