Here we have to calculate the number of rotations made by earth around its own axis in the entire life time of a human being.
The average human life is 50 years .
Each year is 365.5 days
Hence 
=18,275 days
The earth rotates around its own axis in 23 hours 56 minutes and 4 second which is approximately equal to 24 hours or one days.
Hence one rotation takes one days.
⇒18,275 days =18,275 rotations
Hence the total number of rotations made by earth around its own axis in the life time of a average human life time will be 18,275 times
There are
different kinds of forces; applied force, force of gravity, friction force,
normal force, tension force. We will focus on the common forces, applied force
and force of gravity. An applied force is a force that is applied to an object
by another object. The force of gravity is the force with which massively large
objects such as the earth attracts another object towards itself. All objects
of the earth exert a gravity that is directed towards the center of the earth.
Therefore, the force of gravity of the earth is equal to the weight of the
object.
C
Because magnet involves 2 opposite poles so therefore it would have to be C
The period is the time it takes any repeating process
to complete one cycle. You just told us what it is for the
pendulum . . . 6 seconds.
The frequency is the reciprocal of the period. For the pendulum,
that's
1 / (6 sec) = (1/6) per second = 1/6 Hertz .