Which of these can a mirror not do?
a. focus light rays
b. spread light rays
c. refract light rays
d. reflect light rays so they're parallel to each other

Acylinder with a movable piston contains 11.7 moles of a monatomic ideal gas at a pressure of 1.32×10^5 pa. the gas is initially at a temperature of 300 k. an electric heater adds 43200 j of energy into the gas while the piston moves in such a way that the pressure remains constant. cp=20.79 j k^−1 mol^−1 for a monatomic ideal gas, and that the number of gas molecules is equal to avogadro's number (6.022×10^23) times the number of moles of the gas. (a) what is the temperature of the gas after the energy is added? (b) what is the change in volume of the gas? (c) how much work is done by the gas during this process?

In the circuit shown below, with each bulb holding a resistance of 60 ohms, how many amps of current are flowing? express your number as a decimal.

Suppose you increase your walking speed from 7 m/s to 13 m/s in a period of 2 s. what is your acceleration?