Which two fundamental forces are only attractive? O A. Gravitational and strong nuclear
O B. Electromagnetic and weak nuclear
O C. Electromagnetic and strong nuclear
O D. Gravitational and weak nuclear

An asteroid is discovered in a nearly circular orbit around the sun, with an orbital radius that is 2.47 times earth's. what is the asteroid's orbital period, its "year," in terms of earth years?

Ais useful when you need a simple machine to you separate two things. a. lever b. screw c. pulley d. wedge

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.