An australian emu is running due north in a straight line at a speed of 13.0 m/s and slows down to a speed of 10.5 m/s in 4.20 s. (a) what is the magnitude and direction of the bird’s acceleration? (b) assuming that the acceleration remains the same, what is the bird’s velocity after an additional 1.50 s has elapsed?

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.

Atomic nuclei of almost all elements consist of

He latent heat of vaporization for ethyl alcohol is 854 j/g. the amount of energy, rounded to the nearest whole number, needed to change 5.20 grams of ethyl alcohol from a liquid to a gas is