Seth has some $1 bills and some $5 bills. In total he has 6 bills that are worth a total of $22. Write a system of equations and solve to find out how many $5 bills Seth has.

Ineed with 14, 16, 28 and 36 me. we didn't go over them in class so i don't know what to do.

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?

Now max recorded the heights of 500 male humans. he found that the heights were normally distributed around a mean of 177 centimeters. which statements about max’s data must be true? a) the median of max’s data is 250 b) more than half of the data points max recorded were 177 centimeters. c) a data point chosen at random is as likely to be above the mean as it is to be below the mean. d) every height within three standard deviations of the mean is equally likely to be chosen if a data point is selected at random.