What should the dimensions of the inside of the box be so the box is as small as possible?

Answer for 10 points show work you guys in advanced < 3

Meghan has created a diagram of her city with her house, school, store, and gym identified. a. how far is it from the gym to the store? b. meghan also wants to walk to get some exercise, rather than going to the gym. she decides to walk along arc ab. how far will she walk? round to 3 decimal places.

Pls what is the relative minimum of the function? enter your answer in the box