NEED HELP IS THERE SOMEONE CAN HELP ME PLS :)

Modern physics a photon emitted from an excited hydrogen atom has an energy of 3.02 electron volts. which electron energy-level transition would produce this photon? a. n=1 to n=6 b. n=2 to n=6 c. n=6 to n=1 d. n=6 to n=2 i chose b but the correct answer is d can someone tell me why? and what's the difference?

What are two different ways you could find the value of a? explain these methods.

What equation is used to calculate the weight of an object on a plant ?