#### Answer

a): (iii)
b): (ii)
c): (i)

#### Work Step by Step

(a) The derivative $ \frac{d x}{d t}$ is the horizontal rate of change with respect to time.
(b) The derivative $ \frac{d y}{d t}$ is the vertical rate of change with respect to time.
(c) The derivative $ \frac{d y}{d x}$ is the slope of the tangent line to the curve.