Answer:
E means energy
M= Mass
C=speed of light squared (the exponent means squared)
ANSWER

EXPLANATION
Parameters given:
Mass of the student, M = 70 kg
Mass of the textbook, m = 1 kg
Distance, r = 1 m
To find the gravitational force acting between the student and the textbook, apply the formula for gravitational force:

where G = gravitational constant
Therefore, the gravitational force acting between the student and the textbook is:

That is the answer.
The answer is B high pressure.
For rotational equilibrium of the door we can say that torque due to weight of the door must be counter balanced by the torque of external force

here weight will act at mid point of door so its distance is half of the total distance where force is applied
here we know that

now we will have


so our applied force is 72.5 N
Answer:
1 Frequency
2 Wavelength
3 Amplitude
4 Crest
Hope it helps pls mark brainliest