1) 0N... friction opposes the motion of an object, since the block is at rest there is no motion thus no friction
2) F=ma
= (5.5kg)(30m/s)
=165 N
opaque glass does not allow light to pass through it.
Mitochondria breaks down sugar to release energy to the cell.
Answer:
pretty sure for this one, "if the density affected the liquid's ability to retain heat."
Explanation:
a hypothesis should be in "if, then, because.." format, and while this bit of the passage doesnt include all three, it does include one! that bit of the passage would be an incomplete hypothesis.