HELP!! please answer for me.. Offering 62 points :>

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f

Why do astronauts in the space shuttle weigh less?

If an electric circuit is not grounded it is best to reach out and touch it to provide the ground a.true or b.false