Which of the following metals releases hydrogen gas upon reaction with cold and dilute $HNO_3$?

What is the technique of obtaining a large number of plantlets by tissue culture called?

$CrO_3$ dissolves in aqueous $NaOH$ to give:

If $y=y(x)$ is the solution of the differential equation $x\frac{dy}{dx} + 2y = x^2$ satisfying $y(1)=1$,then $y\left(\frac{1}{2}\right)$ is equal to

The equation of the line passing through the point of intersection of the lines $x-3y+2=0$ and $2x+5y-7=0$ and perpendicular to the line $3x+2y+5=0$ is: