Ahot air balloon is traveling vertically upward at a constant speed of 4.5 m/s. when it is 28 m above the ground, a package is released from the balloon. after it is released, for how long is the package in the air? the acceleration of gravity is 9.8 m/s 2 .

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.

Suppose a wire with a current is pushed upward by a magnetic field. how would the wire move if the direction of the current reversed? explain your answer.

What causes the development of most clouds and precipitation in the atmosphere?