Answer: Visible light makes up just a small part of the full electromagnetic spectrum. Electromagnetic waves with shorter wavelengths and higher frequencies include ultraviolet light, X-rays, and gamma rays.
Answer:
a

b

Explanation:
From the question we are told that
The mass of the rock is 
The length of the small object from the rock is 
The length of the small object from the branch 
An image representing this lever set-up is shown on the first uploaded image
Here the small object acts as a fulcrum
The force exerted by the weight of the rock is mathematically evaluated as

substituting values


So at equilibrium the sum of the moment about the fulcrum is mathematically represented as

Here
is very small so
and 
Hence

=> 
substituting values


The mechanical advantage is mathematically evaluated as

substituting values


Velocity is defined as Distance divided by Time.
In other words, V = D/T.
Now that we have our formula, we can solve.
Let's plug in the numbers we have.
We have 12m [East (direction not necessary when solving yet)] for our distance, and 0.15s as our time.
Divide the distance (12 /) by the time (0.15)
12 / 0.15 = 80.
Your velocity is 80 m/s [E]
I hope this helps!
Weight is equivalent to the product of the mass of an object and the strength of the gravitational field.
Using:
F = ma
a = 8.2 / 5
a = 1.64 N/kg
The gravitational field strength is equivalent to 1.64 N/kg.