Which type of wave cannot have compressions and rarefactions?

a) sound
b) transverse
c) mechanical
d) longitudinal

Aplane flies directly between two cities, a and b, which are separated by . from a to b, the plane flies into a headwind. on the return trip from b to a, the wind velocity is unchanged. the trip from b to a takes less than the trip from a to b. what is the airspeed of the plane, assuming it is the same in both directions

What is magnetic flux? explain faraday's law of induction.

What is the most useful equation for electric power?