The least positive integer $n$ for which $(1+i)^n=(1-i)^n$ is

Chemical leaching is useful in the concentration of:

Which one of the following is an example of cleistogamy?

The maximum value of $\frac{\log x}{x}, 0 < x < \infty$ is

$A$ uniform chain of length $L$ is lying on a horizontal table. If the coefficient of friction between the chain and the table top is $\mu$, what is the maximum length of the chain that can hang over the edge of the table without disturbing the rest of the chain on the table?

In the circuit shown in the figure,the current $I$ is: (in $\,A$)