Among the following,the strongest base is

Which of the following represents the correct order of the acidity in the given compounds?

In the figure,the potentiometer wire $AB$ of length $L$ and resistance $9r$ is joined to the cell $D$ of $emf$ $\varepsilon$ and internal resistance $r$. The cell $C$'s $emf$ is $\varepsilon / 2$ and its internal resistance is $2r$. The galvanometer $G$ will show no deflection when the length $AJ$ is

The area of the triangle formed by the lines ${y^2} - 9xy + 18{x^2} = 0$ and $y = 9$ is

Which of the following is an example of a neutral oxide?

In the Sun,the important source of energy is