13) compare primary and secondary succession of an ecosystem. what is the distinction between them?

The metric unit of electrical power is the watt volt ampere ohm

Which of the following are considered noble gases? a. bromine b. neon c. argon d. chlorine

Light traveling in water, nwater = 1.33, strikes a plastic block at an angle of incidence of 51.4°; part of the beam is reflected and part is refracted. if the index of refraction of the plastic is 2.0, what is the angle made by the reflected and refracted beams?