Which of the following is not a Linear Differential Equation?

The order and degree of the following differential equation are, respectively: \(-\frac{d^{4}y}{dx^{4}}+2e^{dy/dx}+y^{2}=0\)

Find the general solution of the differential equation $(x^{3}-3xy^{2})dx=(y^{3}-3x^{2}y)dy$.

The solution for the differential equation \(\log(\frac{dy}{dx})=3x+4y\) is:

(i) Write the order and degree of the given differential equation. (ii) Substituting $V = \pi r^3$ and $S = 2\pi r^2$, we get the differential equation $\frac{dr}{dt} = \frac{2}{3}k$. Solve it, given that $r(0) = 5$ mm. (iii) (a) If it is given that $r = 3$ mm when $t = 1$ hour, find the value of k. Hence, find t for $r = 0$ mm. OR (iii) (b) If it is given that $r = 1$ mm when $t = 1$ hour, find the value of k. Hence, find t for $r = 0$ mm.