Answer:
A and B
Explanation:
The relation between frequency and wavelength is shown below as:

c is the speed of light having value 
Thus, the product of the wavelength and the frequency is constant and equal to 
<u>Option A is correct.</u>
Given, Frequency = 
Thus, Wavelength is:



Also, 1 m =
Å
So,
<u>Wavelength = 3.0 Å</u>
<u>Option B is correct.</u>
As stated above, the speed of electromagnetic radiation is constant. Hence, each radiation of the spectrum travels with same speed.
<u>Option C is incorrect.</u>
The average rate at which the cable does work is 294,000 J/s.
The given parameters:
- <em>mass, m = 3000 kg</em>
- <em>height, h = 200 m</em>
- <em>time of motion, t = 20 s</em>
The average rate at which the cable does work is calculated as follows;

Thus, the average rate at which the cable does work is 294,000 J/s.
Learn more about energy and power here: brainly.com/question/13387946
Answer:
The amount of electrons that flow in the given time is 3.0 C.
Explanation:
An electric current is defined as the ratio of the quantity of charge flowing through a conductor to the time taken.
i.e I =
...................(1)
It is measure in Amperes and can be measured in the laboratory by the use of an ammeter.
In the given question, I = 1.5A, t = 2s, find Q.
From equation 1,
Q = I × t
= 1.5 × 2
= 3.0 Coulombs
The amount of electrons that flow in the given time is 3.0 C.