Erosion that occurs at irregular or varying rates, caused by the differences in the resistance and hardness of surface materials. a. True
b. False

Aplanet of mass m 6.75 x 1024 kg is orbiting in a circular path a star of mass m 2.75 x 1029 kg. the radius of the orbit is r 8.05 x107 km. what is the orbital period (in earth days) of the planet tplanet?

70 give a real life example showing how sensory neurons work with the motor neurons

The electric potential a distance r from a small charge is proportional to what power of the distance from the charge? a. r^-1 b. r c. r^-2 d. r^2