What is the primary source of a sound? A refraction
A medium to carry the signal
A vibration
A frequency

Complete the statement about memory improvement. ( )involves organizing and breaking down information into easier groups to expand capacity. rehearsal is the verbal repetition of information. these techniques are especially important for the improvement of ( ) memory.

An engine undergoes a cycle as shown in the diagram. during a complete cycle the work done by the gas is 28.5×103 j and the energy transferred thermally out is 99.4×103 j. there are 1.5×1024 gas molecules and they have three active degrees of freedom. 6. (6 pts) during which process(es) is energy transferred thermally into the gas? a. 1→2 b. 2→3 c. 4→1 d. 1→2 and 4→1 e. none of the above

What is the increase in density of a medium due to wave travel?