8. What happens when a wave reaches the boundary of a new media?

A. it would reflect back
B. it would continue moving
C. either A or B
D. it would stop

Would it be C?

For incomplete cancellation to occur, opposite pulses must have

A. equal amplitudes
B. different energies
C. equal pulses
D. equal displacements

Would it be B?

8. A AND B would be more correct than A OR B. In most cases the wave is partly reflected and partly gets transmitted to the new medium

The next question choices are also poor. Are you sure you mean INCOMPLETE cancellation? Incomplete cancellation happens most of the time, when amplitudes are unequal