A competitive knitter is knitting a circular place mat. The radius of the mat is given by the formula 605 r(t) = 5- with 7 in centimeters and t in seconds. (t + 11) A. Find the rate at which the area of the mat is increasing. Select an answer B. Use your expression to find the rate at which the area is expanding at t = 3. Round your answer to 2 decimal(s). Select an answer