What is the common name of bread mold?

Drift velocity ${v_d}$ varies with the intensity of the electric field $E$ as per the relation:

The angle between the lines represented by $y^2 \sin^2 \theta - xy \sin^2 \theta + x^2(\cos^2 \theta - 1) = 0$ is

The solution of the differential equation $\frac{dy}{dx} - y \tan x = e^x \sec x$ is

If the radius of a nucleus with mass number $125$ is $1.5 \text{ fermi}$,then the radius of a nucleus with mass number $64$ is: (in $text{ fermi}$)

Nitrobenzene on reduction with zinc and $NH_4Cl$ gives