If $x$ is real,then the value of $\frac{x^2-3x+4}{x^2+3x+4}$ lies in the interval

Identify the incorrect statement among the following:

If the geometric mean between $a$ and $b$ is $\frac{a^{n+1} + b^{n+1}}{a^n + b^n}$,then the value of $n$ is

$A$ magnetized wire of magnetic moment $M$ and length $L$ is bent into an arc of a circle subtending an angle of $60^{\circ}$ at the center. The new magnetic moment is:

Which is the best method to obtain virus-free plants through tissue culture?

Which one of the following frequencies of radiation (in $Hz$) has a wavelength of $600 \ nm$?