Answer: 28.8 m/sec², towards the center of the circle.
Explanation:
By definition, acceleration is defined as the quotient between a change in velocity (in value or direction) over time.
In this case, even the velocity value is constant, is changing direction all the time, so there is an acceleration present.
This acceleration is called the centripetal acceleration, and always aims to the center of the circle, because otherwise the toy car will move in a straight line at constant speed, like is dictated by Newton's First law.
It can be showed that it can be calculated as follows:
a = V² / R = (36.0)² (m/s)² / 45.0 m = 28.8 m/s, pointing towards the center of the circle.