Plutonium-32 has a half-life of 14.2 days. After 99.4 days, how much of what was originally a 499.2 gram sample remains? 14 grams

3.9 grams

35.7 grams

0.71 grams

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

6–48 bananas are to be cooled from 24 to 138c at a rate of 215 kg/h by a refrigeration system. the power input to the refrigerator is 1.4 kw. determine the rate of cooling, in kj/ min, and the cop of the refrigerator. the specific heat of banana above freezing is 3.35 kj/kg·8c.