Which of the following is mismatched?

Let $P(-1, 0)$,$Q(0, 0)$,and $R(3, 3\sqrt{3})$ be three points. Then the equation of the bisector of the angle $\angle PQR$ is

The transformed equation of $3x^2 + 3y^2 + 2xy = 2$,when the coordinate axes are rotated through an angle of $45^{\circ}$,is

Three blocks $A, B$ and $C$ of masses $4\, kg$,$2\, kg$ and $1\, kg$ respectively,are in contact on a frictionless surface,as shown. If a force of $14\, N$ is applied on the $4\, kg$ block,then the contact force between $A$ and $B$ is .......... $N$.

If the lines $3x + 4y - 14 = 0$ and $6x + 8y + 7 = 0$ are both tangents to a circle,then its radius is

Which of the following is a biofertilizer?