How do you find out the maximum velocity of a pendulum, what formula do i use?

An air-standard stirling cycle operates with a maximum pressure of 600 psia and a minimum pressure of 10 psia. the maximum volume of the air is 10 times the minimum volume. the temperature during the heat rejection process is 100°f. calculate the specific heat added to and rejected by this cycle, as well as the net specific work produced by the cycle. use constant specific heats at room temperature. the properties of air at room temperature are r

Unpolarized light of intensity so passes through two sheets of polarizing material whose transmission axes make an angle of 60∘ with each other as shown in the figure. what is the intensity of the transmitted beam, st?

Light from the sun reaches the earth in 8.3 minutes. the velocity is 3.00 x 10^8 m/s. how far is earth from the sun? i know how to get to d = (3 x 10^8 m/s)(498 sec). i just don't know how to get from there to the answer being 1.5 x 10^11 m.