<span>Work: W = Fd. 50(distance) multiplied by 90(force) would equal 4500 J or, answer D</span>
A surface wave is a wave in which particles of the medium undergo a circular motion.
Wave speed = (wavelength) x (frequency)
= (45 meters) x (9 per second)
= 405 meters per second .
To solve this problem we will start from the given concept in which the number of turns is equivalent to the length of the thread per circumference of spool. That is:

Where,
l = length of the thread
= circumference of spool
For \phi we have that,

For l we have that
l = 62.8m
Finally the number of Turns would be,



Therefore the number of turns of thread on the spool are 1000turns.
The first step is the fusion of hydrogen into Deuterium.