Answer:
False
Explanation:
This proposition is false because by example the sun exerts a force over the earth and them are not in contact
I believe the percentage is between 15-20%. Stress is a well known factor that affects the performance of people.
Explanation:
Formula which holds true for a leans with radii
and
and index refraction n is given as follows.
Since, the lens is immersed in liquid with index of refraction
. Therefore, focal length obeys the following.
and,
or,
= 32.4 cm
Using thin lens equation, we will find the focal length as follows.

Hence, image distance can be calculated as follows.


= 47.9 cm
Therefore, we can conclude that the focal length of the lens in water is 47.9 cm.