Answer:
The ratio of the model size is 1 : 2000
Explanation:
Given
Real Diameter = 0.012 um
Scale Diameter = 24 um
Required
Determine the scale ratio
The scale ratio is calculated as follows;

Substitute values for real and scale measurements

Divide the numerator and the denominator by 0012um

Represent as ratio

<em>Hence, the ratio of the model size is 1 : 2000</em>
Red shift in the spectrum of a star is always taken to mean that the source of the light is moving away from us.
That's the whole basis for the notion of the expanding universe, since we don't know of any other mechanism that can shift light toward longer wavelengths.
If you're willing to consider fractions or decimals,
then there are an infinite number of answers.
Like (2.5 x 160), and (15 x 26-2/3).
If you want to stick to only whole numbers,
then these 8 combinations do:
1, 400
2, 200
4, 100
5, 80
8, 50
10, 40
16, 25
20, 20
The man is holding the suitcase at the same height above the surface of earth. So the gravitation potential energy remains the same.
<span>work done is force * displacement = weight * 0 = 0</span>