We get the clearest image if there is no magnification. When we have no magnification the image and real object have the same size.
If we look at the diagram that I attached we can see that:

Two triangles that I marked are similar and from this we get:

The image and the object must have the same height so we get:

This tells how far the screen should be from the lens.
The position of the screen on the optical bench is:
<span><span>Use the periodic table and your knowledge of isotopes to complete these statements.
When polonium-210 emits an alpha particle, the child isotope has an atomic mass of </span><span> ⇒ 206</span>.</span>
<span><span>I-131 undergoes beta-minus decay. The chemical symbol for the new element is </span><span> ⇒ Xe</span>.</span>
<span><span>Fluorine-18 undergoes beta-plus decay. The child isotope has an atomic mass of </span><span> ⇒ 18</span>.</span>
Answer:
longer than
Explanation:
given,
time of nap = 10 min
speed of orbiting earth = 8000 m/s
c is the speed of light
using the equation of time dilation

now inserting all the values


t' = 10.001 s
on solving the above equation we will get a value greater than 10minutes.
hence, On earth time of nap measured will be longer than 10 min