$A$ weight $W$ can be hung in any of the following four ways by a string of the same type. In which case is the string most likely to break?

The sulphate of a metal $M$ contains $9.87 \%$ of $M$. This sulphate is isomorphous with $ZnSO_4 \cdot 7H_2O$. The atomic weight of $M$ is: (in $.3$)

In an experiment with $15$ observations of $x$,the results $\sum x^2 = 2830$ and $\sum x = 170$ are obtained. If one observation $20$ is found to be incorrect and is replaced by the correct observation $30$,what is the correct variance?

Which of the following is the pair of biofertilizers?

The approximate value of $\int_1^3 \frac{dx}{2+3x}$ using Simpson's rule and dividing the interval $[1, 3]$ into two equal parts is

$A$ solid reflects incident light and its electrical conductivity decreases with temperature. The binding in this solid is: