Assume that the wavelengths of photosyntheticallyactive radiations (PAR) are uniformly distributed at integernanometers in the red spectrum from 675 to 700 nm. a. What are the mean and variance of the wavelength distributionfor this radiation?b. If the wavelengths are uniformly distributed at integernanometers from 75 to 100 nanometers, how do the meanand variance of the wavelength distribution compare to theprevious part? Explain.

What is a good example of instantaneous speed

Apositive charge moves in the direction of an electric field. which of the following statements are true? check all that apply. check all that apply. 1.the potential energy associated with the charge decreases. 2. the electric field does positive work on the charge. 3. the electric field does negative work on the charge. 4. the potential energy associated with the charge increases. 5. the electric field does not do any work on the charge. 6. the amount of work done on the charge cannot be determined without additional information.

Convection currents are caused by differences in what two things?