# Mandy's on the run!

Mandy is really into physics. Sadly, she can't afford the wonderful Feynman Lectures on Physics. But her interest was so strong that one day she decided to steal the books from the university library. She then drove away and has now been gone for 24 hours. Given that:

• She stops 30min every 3h to rest.

• She always drives at a speed of 108km/h except when she slows down/speeds up (at a constant rate of $$\pm 1 N.{ kg }^{ -1 }$$ ) before and after each pause.

Consider a circle, whose origin is the library, such that Mandy has probability $$0$$ of being spotted anywhere outside that circle. Then what is (in km) the minimum radius $$\tilde { R }$$ of the circle?

Details and assumptions:

• Mandy always travels on flat land.

• The time it takes to slow down/speed up is taken off driving time.