Which of the following is an example of a contact force?

a. a magnet moving a metal object
b. gravity causing a rock to move
c. a person pushing a box across the floor
d. a person falling out of the sky

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

What effect might melting sea ice have for people who live in coastal areas?

Which of the following units is not an official si unit? mole liter kilogram ampere