$\"\"$

(a)

The $\"\"$ -axis is starting line.

Luna and Ruby are run parallel to the $\"\"$ -axis.

The parametric equations are,

Luna: $\"\"$ and $\"\"$ .

Ruby: $\"\"$ and $\"\"$ .

$\"\"$

(b) Luna wins the race.

$\"\"$

(a) Luna: $\"\"$ and $\"\"$ .

Ruby: $\"\"$ and $\"\"$ .

(b) ) Luna wins the race.