Help this girl out. This maths is killing me

Suppose that x and y are both differentiable functions of t and are related by the given equation. use implicit differentiation with respect to t to determine startfraction dy over dt endfraction in terms of x, y, and startfraction dx over dt endfraction .

Write the converse of the following statement: if the trees have no leaves, then it is fall. if the trees have no leaves, then it is fall. the trees have no leaves, therefore it is fall. it is fall since the trees have no leaves. if it is fall, then the trees have no leaves.

A20? -foot ladder is placed against a vertical wall of a? building, with the bottom of the ladder standing on level ground 19 feet from the base of the building. how high up the wall does the ladder? reach?