In a class of 300 students, every student reads 5 news papers and every news paper is read by 60 students. Then the number of newspapers is

The maximum value of $\frac{\log x}{x}$ is

Derivative of $\mathrm{e}^x$ w.r.t. $\sqrt{x}$ is

The curve satisfying the differential equation $y \mathrm{~d} x-\left(x+3 y^2\right) \mathrm{dy}=0$ and passing through the point $(1,1)$ also passes through the point