What is the correct identity for cos(pi/2 - theta)

You are on a cycling trip around europe with friends. you check the weather forecast for the first week. these are the temperatures for the week. sun mon tues wed thurs fri sat 16°c 20°c 24°c 28°c 28°c 23°c 15°c what is the mean temperature forecast for the week?

Which of the following would be a good name for the function that takes the weight of a box and returns the energy needed to lift it?

Which expression do you get when you eliminate the negative exponents of 4a^2 b^216a^-3 b