I did try to solve. I hope it is correct, below is the solution:
<span>put everything in s.i units
then the answer what u wrote is acceleration to get is divide by mass(80)
G=6.011*10^-11
M=6*10^24
R=6.4*10^6
m=80
</span>
Hope it helps.
The speed of the spring when it is released is 3.5 m/s.
The given parameters:
- <em>Mass of the block, m = 2.5 kg</em>
- <em>Spring constant, k = 56 N/m</em>
- <em>Extension of the spring, x = 0.75 m</em>
The speed of the spring when it is released is calculated by applying the principle of conservation of energy as follows;

Thus, the speed of the spring when it is released is 3.5 m/s.
Learn more about conservation of energy here: brainly.com/question/166559
Answer: 5 m
Explanation:
We have the following data:
is the intensity of the sound at 7.5 m from the source
is the distance at which the intensity
was measured
is the intensity of the sound at
from the source
We have to find 
Since the object is radiating the signal uniformly in all directions, we can use the <u>Inverse Square Law for Intensity:</u>

Isolating
:


This is the distance at which the intensity is the "threshold of pain"
Now, we have to substract this value to
to find how much closer to the source can we move:

Answer:
Mass of shot (m) = 4 kg
Explanation:
Given:
Velocity (v) = 15 m/s
Mechanical kinetic energy (K.E) = 450 J
Find:
Mass of shot (m) = ?
Computation:
Mechanical kinetic energy (K.E) = 1/2mv²
Mechanical kinetic energy (K.E) = [1/2](m)(15)²
450 = [1/2](m)(15)²
900 = 225 m
Mass of shot (m) = 4 kg
[Assuming that you've written 3.40 kg in 'a', and not 3.90 kg]
(a) 3,400 g x <u>0.001</u> = 3.40 kg [converting grams to kilograms]
(b) 220 cm x <u>0.01</u> = <u>2.2</u> m [converting centimeters to meters]
(c) 9.42 kg x <u>1000</u> = <u>9420</u> g [converting kilograms to grams]
(d) 6.53 m x <u>100</u> = <u>653</u> cm [converting meters to centimeters]