List a function that's it's own inverse

Me solve this problem, and someone clearly explain to me how to solve it.1.) use the value of the discriminant to determine if the given trinomials has 2 real solutions, 1 real solution, or no real solutions.a.  x2  − 4x  − 7 = 0b. 4r2  + 11r  − 3 = 0c. 3m2  + 7 = 0d.  t2  + 2t  + 1 = 0

The cone in the diagram has the same height and base area as the prism. what is the ratio of the volume of the cone to the volume of the prism? h hl base area-b base area =b volume of cone_1 volume of prism 2 volume of cone 1 volume of prism 3 volume of cone 2 volume of prism 3 oc. od. volume of cone volume of prism e. volume of cone volume of prism 3 2

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?