A simple definition of cells

Which statement best describes the relationship between period and frequency of light waves? a) in wave b the period increases and the frequency decreases from wave a. b) in wave a the period increases and the frequency decreases from wave b. c) in wave b the period is shorter and the frequency is greater than in wave a. d) in wave a the period is shorter and the frequency is greater than in wave b.

Nonpoint source pollution is difficult to control because it

Will mark brainliest how many electrons can be held in the energy level n = 4?