How do you solve and what is the answer?

Can someone with this one pre-calc question? the finishing time for a runner completing the 200-meter dash is affected by the tail-wind speed, s. the change, t, in a runner's performance is modeled by the function shown below: t= 0.0119s^2 - 0.308s - 0.0003 predict the change in a runner's finishing time with a wind speed of 3 meters/second. note: a negative answer means the runner finishes with a lower time. round to the nearest hundredth.

Jacob signs up to work for 2 1/2 hours at the school carnival. if each work shift is 3/4 hour, how many shifts will jacob work? (i just want to double check : |, for anybody that responds! : )

You give a $4 tip for a meal that cost $22. approximately what percent of the bill was your tip?