A projectile is launched from a hole in the ground one foot deep. Its height follows the equation h = -16t^2 + 8t -1. Use factoring by perfect-squares to find the time when the projectile lands back on the ground. (Hint: Landing on the ground means projectile height is zero.)

Mr.walker is looking at the fundraiser totals for the last five years , how does the mean of the totals compare to the median?

The ages of personnel in the accounting department of a large company are normally distributed with a standard deviation of 7 years. there is a 0.02275 probability that the age of any randomly chosen person in the department is less than 22 and 0.15866 probabilty that the age of any randomly chosen person is greater than 43. what is the mean of this distribution?

Ribbon a is 1/3 meters long. it is 2/5 meters shorter than ribbon b. what's the total length of 2 ribbons?