(8marks) 02. The rate of cooling stearm is given by de-k,where k is a constant. If θ-600 when t-2 minutes and e-soo when t-5 minutes, determine the time taken for θ to fall to 40° correct to the nearest second. (8marks) Q3. Find the radius of curvature of the part of a surface when determine the surface a) dx d'y dx tension of a liquid is given by Find the radius of curvature of the part of the surface having parametric equation a, x=3t,y=3/tat the poit t = 1 /2 (8marks) Q4. In a oil rig a thermodynamic system , K = Ae--, where R,k and A are constants (8marks) Find ak ãad