The normal healing of wounds can be modeled by an exponential function. If A₀ represents the original area of the wound and if A equals the area of the wound, then the function

A(n) = A₀e^-0.35n

describes the area of a wound after n days following an injury when no infection is present to retard the healing. Suppose that a wound initially had an area of 100 square millimeters.

(a) If healing is taking place, after how many days will the wound be one-half its original size?

(b) How long before the wound is 10% of its original size?