Answer
The distance traveled in the first four seconds is 8.0 furlongs.
Work Step by Step
The distance traveled is proportional to the square of the time. That is:
$d = ct^2$, where $c$ is a constant.
An object travels 2.0 furlongs in the first 2.0 seconds. We can use this information to find the constant $c$.
$d = ct^2$
$c = \frac{d}{t^2}$
$c = \frac{2.0~furlongs}{(2.0~s)^2}$
$c = 0.5~furlong/s^2$
We can find the distance in the first 4.0 seconds.
$d = ct^2$
$d = (0.5~furlong/s^2)(4.0~s)^2$
$d = 8~furlongs$
The distance traveled in the first four seconds is 8.0 furlongs.
