if they have air in their lungs or are less dense than water
I think the answer is false. not the WHOLE world, probably just a lot of it.
Answer:
The ancient Greeks counted the Earth's Moon and Sun as planets along with Mercury, Venus, Mars, Jupiter, and Saturn. Earth was not considered a planet, but rather was thought to be the central object around which all the other celestial objects orbited. ...... Jupiter is composed of gases — hydrogen and helium, mostly — all ... the largest planet in the solar system, the gas giant just doesn't have ... But unlike the sun, it lacks the necessary amount to begin fusion, the process that fuels a star. ... to 80 times more massive than it is at present to be considered a star.
Answer:
18.5 cm
Explanation:
From;
1/u + 1/v = 1/f
Where;
u= object distance = 86cm
image height = 23 cm
Radius of curvature = 37 cm
The radius of curvature (r) is the radius of the sphere of which the mirror forms a part.
Focal length (f) = radius of curvature (r)/2 = 37cm/2 = 18.5 cm
Therefore, the focal length of the mirror is 18.5 cm