For the differential equation $\dfrac{d^3y}{dx^3} + \cos\left(\dfrac{d^2y}{dx^2}\right) = 0$, which of the following is true ?

If water at $100^\circ\text{C}$ cools in 10 minutes to $80^\circ\text{C}$ and to $65^\circ\text{C}$ in the next 10 minutes, then the room temperature will be ...

The equation of the curve passing through the point (0, 1) and having a slope of the tangent at point $P(x, y)$ is equal to $\dfrac{y}{x + y}$, is

If $f(x)$ is a polynomial such that $f(x) = [f'(x)]^2$ and $f(2) = 0$, then $f(-2) = \ldots$