Well 200 doubled or (x2)=400 if that’s what it means
Beat frequency is given by the difference of two frequencies played together
given that
Now
As you go from Radio waves across to Gamma eats : Wavelength decreases and frequency and energy increase.
The flashlight is powered by one or more batteries.
Batteries supply Direct current (DC) .
That depends on a few things that you haven't told us about the setup.
So I'm going to assume one of them, and then give you the answer
in terms of another one:
-- Assume a Class-I lever . . . the fulcrum is between the load and the effort.
-- Then the effort needed to lift the load is
(the weight of the load) x (13 / the distance between the fulcrum and the effort)
