Think of the cell membrane as a net and the nutrients are the perfect fit to fall through it. Where the waste is not the right size and will not fit through the holes of the net.
A. Cause and effect.
Explanation:
An experiment can prove cause and effect in a study unlike observational studies.
- Observational studies is a non-experimental system of investigation.
- It helps to identify the causes(independent variable) and the effect(dependent variables).
- In observational studies, the variables cannot be controlled and so it is difficult to prove the cause and effect.
- An experiment can prove cause and effect because the parameters are tested and can be controlled.
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Total hours is 3.35 hours
<u>Explanation:</u>
Given:
convert 3 hours 21 minutes to decimal hours
We know:
1 hour = 60 minutes
and
1 minute = 60 seconds
1 minute = 1 / 60 hours
So,
21 minutes = 
= 0.35 hours
Total hours would be = 3 hours + 0.35 hours
= 3.35 hours
Therefore, total hours is 3.35 hours
Protects the earth from UV radiation.
Hi there!
Recall the equation for spring potential energy:

k = Spring constant (N/m)
x = extension of spring from equilibrium (m)
PE = Potential Energy (J)
Plug in the given values:
