The function $f(x)=x^3-3 x$ is ............

If $x=\sin \theta, y=\sin ^3 \theta$ then $\frac{d^2 y}{d x^2}$ at $\theta=\frac{\pi}{2}$ is ............

The area of the region enclosed between pair of the lines $x y=0$ and the lines $x y+5 x-4 y-20=0$, is .............

If three dices are thrown then the probability that the sum of the numbers on their uppermost faces to be atleast 5 is