4) a 56.9 kg slider descends an 8.21-meter high hill, encountering a friction force of 11.7 n.; the slider descends to a distance of 90m on the downhill.

not really sure but thinking 1.54 mm/us

science is a systematic and logical approach to discovering how things in the universe work. true to this definition, science aims for measurable results through testing and analysis. science is based on fact, not opinion or preferences. the process of science is designed to challenge ideas through research.

explanation:

heats surface water up

we're given that v₀ = 0 and a = 5.4 m/s². therefore, since v = at + v₀ for constant acceleration the equation for velocity is

after 28s,

m/s

which i would round to 150 m/s as my final answer