Answer:
I'd say C is the answer they want, though my pedantic side wants to argue for B being true as well.
Answer:
f = 19,877 cm and P = 5D
Explanation:
This is a lens focal length exercise, which must be solved with the optical constructor equation
1 / f = 1 / p + 1 / q
where f is the focal length, p is the distance to the object and q is the distance to the image.
In this case the object is placed p = 25 cm from the eye, to be able to see it clearly the image must be at q = 97 cm from the eye
let's calculate
1 / f = 1/97 + 1/25
1 / f = 0.05
f = 19,877 cm
the power of a lens is defined by the inverse of the focal length in meters
P = 1 / f
P = 1 / 19,877 10-2
P = 5D
Answer:

Explanation:
<u>Density
</u>
The density of a substance is the mass per unit volume. The density varies with temperature and pressure.
The formula to calculate the density of a substance of mass (m) and volume (V) is:

The cube has a mass of m=3.75 g and a volume of V=3 ml, thus the density is:


Since 1 kg=1000 mg and 1 lt = 1000 ml, the density has the same value but with different units:

This is due to the tilt of the earth on its axis. Although the Sun shines on Earth, because of how the Earth is tilted, the equator is more directly hit compared to places found on the poles. The poles are hit at an angle, therefore the sunlight they receive is lesser than the places at the equator.