Need some with a question in pre-calculus

The table shows the results of three plays in a football game. what is the net result of the three plays? football game 1st play 5 yards 2nd play -9 yards 3rd play 12 yards

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution

The path traveled by a bottlenose dolphin as it jumps out of water is modeled by the equation y=-0.4+3x, where t is the height above water and x is the horizontal distance in feet. if a beam of light is shone upward at an angle modeled by the equation x+y=10, at what height from the waters surface will the beam of light hit the dolphin