(a) Determine (1) the order, (ii) unknown function (dependent variable), (iii) the independent variable and (iv) specify if the following equations are linear: dat dt y sin (y) dy2 'dy + tey +1 (b) Based on the uniqueness and existence theorem, determine whether a solution for given differential equation below exist. dy 1 3x3 + -y = where y(1) = 1 x-1 dxx