How much of the matter in the universe is comprised of atoms?

a. 1%

b. 100%

c. 30%

d. 99%

The number of passengers who arrive at the platform of a subway station for the 10 am train is a random variable with a mean of 120 and a variance of 16. find the lower bound of the probability that there will be between 100 and 140 passengers (round off to second decimal place).

Refrigerant-134a flows through a carnot heat pump cycle at 0.5 kg/s. it is known that the maximum absolute temperature in the cycle is 1.1 times the minimum absolute temperature, and the net power input to the cycle is 2.5 kw. if the refrigerant changes from a saturated vapor to a saturated liquid during the heat rejection process, determine the maximum magnitude of the enthalpy of vaporization for this process in kj/kg (with 3 significant figures).

Atruck with 34-in.-diameter wheels is traveling at 55 mi/h. find the angular speed of the wheels in rad/min, *hint convert miles to inches & hours to minutes: