Which fungus has proven to be an effective biological control agent?

The voltage of an $AC$ source varies with time according to the equation $V = 100 \sin(100\pi t) \cos(100\pi t)$,where $t$ is in seconds and $V$ is in volts. Then:

The first diffraction minimum due to a single slit diffraction is seen at $\theta = 30^o$ for light of wavelength $5000 \, \mathring{A}$ falling perpendicularly on the slit. The width of the slit is

If the roots of the equation $(b - c)x^2 + (c - a)x + (a - b) = 0$ are equal,then $a, b, c$ are in which progression?

$A$ bar magnet of magnetic moment $M$ and moment of inertia $I$ is freely suspended such that the magnetic axial line is in the direction of the magnetic meridian. If the magnet is displaced by a very small angle $\theta$,the angular acceleration is (Magnetic induction of earth's horizontal field $= B_H$)

If $\frac{x^3}{(2x-1)(x+2)(x-3)} = A + \frac{B}{2x-1} + \frac{C}{x+2} + \frac{D}{x-3}$,then $A$ is equal to