What type of roadway has the highest number of hazards per mile?

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

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?

Most of the volume of an atom is occupied by the