8. a boy pulls a 20.0-kg box with a 140-n force at 30° above a horizontal surface. if the coefficient of kinetic friction between the box and the horizontal surface is 0.25 and the box is pulled a distance of 28.0 m, what is the net work done on the box?

kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.

the right answer is 0.3 meters per second

the aurora is formed when charged particles emitted from the sun during a solar flare penetrate the earth's magnetic shield and collide with atoms and molecules in our atmosphere. these collisions result in countless little bursts of light, called photons, which make up the aurora.

auroras are generated by charged solar particles hitting molecules in earth's atmosphere. this usually happens in high latitudes, because our planet’s magnetic field tends to funnel these particles toward the poles. that’s why it can be experienced in northern ohio.

answer a fan shaped mass of sediment deposited at the base of a mountain front do to an abrupt change in stream gradient;