Select the correct answer In which disorder does a person find it difficult to fall
asleep ot stay asleep for a long time
A. somnambulism
B. narcolepsy
C. insomnia
D. sleep apnea

Power can be defined as a. the distance over which work was done. b. how much work can be done in a given time. c. all the work in an given area. d. the energy required to do work.

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.

Aproton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?