Circle the classifications which apply to each of the following differential equations (a) ty′ = y Separable Linear Nonlinear Exact (b) (2t + y) + (t − 6)dy dt = 0 Separable Linear Nonlinear Exact (c) y′ = cos(ty) Separable Linear Nonlinear Exact (d) y′ = t2 Separable Linear Nonlinear Exact (e) y′ = 2ty 1+y Separable Linear Nonlinear Exact