Acrescent moon appears when
a) the moon is not visible from the earth
b) less than half of the lit side of the moon is facing the earth
c) more than one half of the lit side of the moon faces the earth
d) the entire lit side of the moon faces the earth

k2s for potassium sulphide

3. dark matter

empty space could also be a simple vacuum

the force represented by vector a is normal force. if the hockey puck is moving to the right, when it is hit with a significant force by the hockey stick the puck will move off in a different direction. correct on edge.