Which of the following is true?

question 5 options:

a. the earth exerts a gravitational force on the moon, but the moon does not exert a gravitational force on the earth.

b. the earth and moon both exert gravitational forces on each other.

c. the moon exerts a gravitational force on the earth, but the earth does not exert a gravitational force on the moon.

d. the earth and moon do not exert gravitational forces.

Antireflective coatings on solar cells are often made by applying a thin film of silicon nitride (sinx), which has an index of refractive of 1.2, on the top of the silicon solar cell, which has a refractive index of about 3.5. however, the sun emits radiation of various wavelengths which the solar cell absorbs, and the antireflective coating can only absolutely minimize the reflection of one of these wavelengths. the coating thickness is chosen to reduce the reflection of green/yellow light (e = 2.2 ev), which is the most intense color in the solar spectrum (shown below). which of the following coatings would minimize reflection of green/yellow light? the answer is 820 nm how? what is the angular width of the central maximum of an electron traveling at 2 x 108 m/s going through a single slit of width 1 mm.

Aball horizontally thrown from a cliff at 8m/s

First to answer will be the brainliest i need the answer asap