[OU.04]Two groups of scientists got different results while studying about the expansion of the universe. What do the two results most likely indicate? the ideas of both groups of scientists are invalid
all scientists do not have access to equally accurate data
there are several testable ideas to describe the origin of the universe
it is impossible to have a single acceptable theory about the universe

Under the action of a constant force an object accelerates at 7.8 m/s2. what will the acceleration be if (a) the force is halved? (b) the object's mass is halved? (c) the force and the object's mass are both halved? (d) the force is halved and the object's mass is doubled?

Complete these sentences. if a roller coaster train has a potential energy of 1,500 j and a kinetic energy of 500 j as it starts to travel downhill, its total energy isj. once the roller coaster train gets closer to the bottom of the hill, its kinetic energy increases to 1,100 j, and its potential energy decreases to j. when the train reaches the bottom of the track and is traveling along the ground, its kinetic energy isj.

What kind of waves require a medium to travel? question 6 options: light waves mechanical waves all waves need a medium to travel electromagnetic waves