Achild is on a pogo stick. at the top of her jump, her kinetic energy (ke) = 0 j, her gravitational potential energy (gpe) = 100 j, and the potential energy in the spring (spe) = 0 j. at the bottom of the jump, immediately before the child jumps again, what do ke, gpe, and spe equal? (assume a closed system.
a) ke = 0 j, gpe = 100 j, and spe = 0 j
b) ke = 50 j, gpe = 0 j, and spe = 50 j
c) ke = 100 j, gpe = 0 j, and spe = 0 j
d) ke = 0 j, gpe = 0 j, and spe = 100 j

Yasmin's teacher asks her to make a supersaturated saline solution. her teacher tells her that the solubility of the salt is 360 g/l at room temperature (25 °c). how can yasmin make a supersaturated saline solution? she can add 380 g of salt to 1 l of hot water (75 °c) and stir until all the salt dissolves. then, she can carefully cool the solution to room temperature (25 °c). she can add 360 g of salt to 1 l of room temperature water (25 °c) and stir the solution until all the salt dissolves. she can add 380 g of salt to 1 l of cold water (5 °c) and stir the solution until most of the salt dissolves. then, she can carefully heat the solution to room temperature (25 °c). she can add 380 g of salt to 1 l of room temperature water (25 °c) and let the solution sit for 24 hours, so the salt dissolves.