A Star is said to be born when ? a) A red giant collapses on itself and becomes a black hole
b) a protostar reaches a temperature high enough for nuclear fusion to begin
c) pressure within a protostar becomes so great that a supernova occurs
d) a dark, cool interstellar cloud begins to contract

What statements accurately describe atoms

Suppose you have a box. which of these is not necessarily a true statement regarding the relationship between the force applied to the box, the work done on the box, and the distance the box is moved? a. if the box is not moved, no force is being applied to the box. b. if no force is applied to the box, no work is done on the box. c. if work is done on the box, then a force is applied to the box. d. if work is done on the box, then the box is moved a distance.

Yvette hangs a 2.4kg bird feeder in the middle of a rope tied between two trees. the feeder creates a tension of 480 n in each side of the the rope.