What types of cells are likely to have lots of smooth ER?

An insurance company wants to know if the average speed at which men drive cars is higher than that of women drivers. the company took a random sample of 27 cars driven by men on a highway and found the mean speed to be 72 miles per hour with a standard deviation of 2.2 miles per hour. another sample of 18 cars driven by women on the same highway gave a mean speed of 68 miles per hour with a standard deviation of 2.5 miles per hour. assume that the speeds at which all men and all women drive cars on this highway are both approximately normally distributed with unknown and unequal population standard deviations.

Determine the amount of work done when a crane lifts a 100-n block form 2m above the ground to 6m above the ground

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e