2. There is a circle whose radius r is changing with time t. We are interested in the area A of a sector of this circle whose central angle 6 is also changing with time 15. Here are the formulae by which r and I9 are changing: at) = 5:2 + 2, m) = g 315 Recall that the area of a sector in a circle is given by the formula %r26 where the central angle 19 is measured in radians. (a) (2 marks) What is the initial area of this sector? That is: what is A when t = 0? (b) (3 marks) How fast is the area A changing at t = 1