Answer:
C
Explanation:
Answer A: A surface wave is a wave that travels along the surface of a medium.
Answer B, C: Electromagnetic waves are waves that have no medium to travel whereas mechanical waves need a medium for its transmission.
Answer D: The sentence in the answer D does not fit to the blank in the definition ( of the question )
......
Hope this answer can help you.

<u>Hydroelectric power,</u> also called hydropower is the electricity produced from generators driven by turbines that convert the potential energy of falling or fast-flowing water into mechanical energy.
Answer:
Immediate, potential
Explanation:
In america there are many safety council .in which drivers are trained. According to american safety council in america the drivers are trained in such a way that they can ahead two seconds so that there will not be any immediate hazards and 10 to 12 seconds down the road for potential hazards
So in the blanks there will be immediate and potential
Answer:
t should be 3.57 second
Explanation:
Formula used is v = u+at
In which v is final velocity, u is initial velocity, a is acceleration and t is time.
Substitute each of the info given into the formula and calculate.
49 = 24 + (7)t
t = 3.57s