Carbon tetrachloride (n=1.46) is poured into a container made of crown glass (n= 1.52). If a
light ray in the glass is incident on the glass-to-liquid boundary and makes an angle of 30.0°
with the normal, what is the angle of the corresponding refracted ray with respect to the
normal?

Which statement is true? a) the work done to lift an object 6 meters is greater than the gravitational potential energy it gains. b) the work required to push an object is less than the work required to pull an object the same distance. c) the work required to raise an object to a height is equal to the gravitational potential energy the object gains. d) the work done against gravity to lift an object straight up is greater than the work required to roll it up a ramp.