When you ask for "joules per second", you're asking for "watts".
The rate of energy "transfer" is 'power'. In this case, the light bulb
transfers energy out of the electrical circuit and into the space
around it, in the form of light and heat radiation.
Electrical power = (voltage) x (current) =
(6 volts) x (0.5 ampere) =
3 watts = 3 joules per second.
Imma guess A! Idk if it’s 100% correct tho so I’d check that!
Answer:
Part a) 
Part b) 
Explanation:
Part a) what is its frequency, in rev/s
we have that
An old-fashioned LP record rotates at 33 1/3 RPM
so

Convert mixed number to an improper fraction

Remember that

Convert rev/min to rev/sec

Simplify

Part b) what is it period, in seconds
we know that
The period is the reciprocal of the frequency
therefore
the frequency is

If your machine has a mechanical advantage of 2.5, then WHATEVER force you apply to the input, the force at the output will be 2.5 times as great.
If you apply 1 newton to the machine's input, the output force is
(2.5 x 1 newton) = 2.5 newtons.
If you apply 120 newtons to the machine's input, the output force is
(2.5 x 120 newtons) = 300 newtons.
I think that this is false but I am not sure