In a double-slit arrangement the slits are separated by a distance equal to 100 times the wavelength of the light passing through the slits. What is the angular separation in radians between the central maximum and an adjacent maximum?

0.01 rad

Explanation:

For a double-slit experiment, we have that dsinθ = nλ. The separation between the central maximum and an adjacent maximum is when n = 1

dsinθ = λ

The angular separation θ = sin⁻¹(λ/d)

now d = 100λ

θ = sin⁻¹(λ/100λ) = sin⁻¹(0.01) = 0.573°

θ = 0.573° × π/180 = 0.01 rad

i wanna say it’s between b and d, leaning more towards b.

it has to be b, about 97 percent.