A stone dropped into a still pond sends out a circular ripple whose radius increases at a constant rate of ft/s. How rapidly is the area enclosed by the ripple increasing at the end of s?.

If an inclined plane is 5 m long and 2 m high, what is its mechanical advantage? a. 2.5 b. 3 c. 7 d. 10

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?

Acar drives toward the right over the top of a hill, as shown below. which arrow represents the centripetal acceleration? w x y z