Two identical moons are orbiting a planet. moon a is close and moon b is farther away. which moon do you think pulls with more gravitational force on the surface of the planet?
a. moon a
b. moon b
c. both the same

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?