Please help asap on Edpuzzle

Janet drove 300 miles in 4.5 hours. write an equation to find the rate at which she was traveling

If the altitude is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other. which set of triangles shows the similar triangles created by the altitude in the diagram?

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?