Adriver traveling at 30.0 m/s presses the brakes decelerates at -8.80 m/s^2. how much time, in second, does it take her to come to a full stop?

It takes her 3.409 seconds to make a full stop.

Explanation:

The time it takes to make a full stop can be determined by the equation of velocity for a Uniformly Accelerated Rectilinear Motion:

 (1)

Where is the final velocity, is the initial velocity, a is the acceleration and t is the time.

Equation (1) can be rewritten in terms of t:

 (2)  

For this particular case the final velocity will be equal to zero ():

So it takes her 3.409 seconds to make a full stop.

the moving of the box is a result of centripetal force. think of that  as a car or a truck in this case creates a turn, the force of friction performing upon the turned wheels of the car runs centripetal force obligatory for circular motion for the things inside it.