Apparent brightness depends on which two properties? A. Distance and temperature
B. Luminosity and distance
C. Luminosity and temperature
D. Luminosity and size

I believe it is luminosity and distance

Explanation:

So B

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.