Sunsets are red because a. the longest path of sunlight through the atmosphere is at sunset or sunrise. b. a lot of high-frequency light is scattered by the atmosphere. c. blue light from the sun is scattered by earth's atmosphere. d. all of the above e. none of the above

The specific heat of silver is 0.057 calories/gram°c. if 10.0 grams of silver were heated and the temperature of the sample changed by 20.0°c, how many calories of heat energy were absorbed by the sample?

Which statement correctly describes a step-up transformer? a. it increases the amount of electric energy available. b. it increases the voltage of an electric current. c. it changes direct current into alternating current. d. it has more loops of wire in its primary coil.

What is the coefficient of kinetic friction μk between the block and the tabletop?