4 (a) In the framework ABCD, BD = 3 m. BDAˆ = 27°, BCDˆ = 41°. D BCˆ and DABˆ are right angles. (i) Find AD. (ii) Find CD. (b) In triangle PQR, PQ = 3 m and QR = 5 m. The area of triangle PQR = 6 m^2. Find the two possible values of PQRˆ.