How many calories are produced when 50 ml of water is raised from 22 degrees celsius to 52 degrees celsius? Help it’s due today

Ineed the answer to question 1 , i’m desperate

What object a collides with object b and bounces back its final momentum is?

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