Which insecticide is used for termite control in buildings?

The image of the point $(3, 2, 1)$ in the plane $2x - y + 3z = 7$ is

If the angle of intersection at a point where the two circles with radii $5 \ cm$ and $12 \ cm$ intersect is $90^{\circ}$,then the length (in $cm$) of their common chord is

Which of the following statements is $NOT$ correct?

$10\, g$ of ice at $-20^{\circ}C$ is dropped into a calorimeter containing $10\, g$ of water at $10^{\circ}C$. The specific heat of water is twice that of ice. When equilibrium is reached,the calorimeter will contain:

Dividing the interval $[0,6]$ into $6$ equal parts and by using the trapezoidal rule, the value of $\int_0^6 x^3 dx$ is approximately: