Which reagent is commonly used in titration to determine the hardness of water?

Which one of the following pairs is correctly matched with regard to the codon and the amino acid coded by it?

Select the correct option with respect to the age pyramids shown in the image.

Which of the following glands is associated with the occurrence of sarcoma-type cancer?

The electronic configurations of $Cr^{2+}, Mn^{2+}, Fe^{2+},$ and $Ni^{2+}$ are $3d^4, 3d^5, 3d^6,$ and $3d^8$ respectively. Which one of the following aqua complexes will exhibit the minimum paramagnetic behavior?

$A$ current-carrying solenoid is approaching a conducting loop as shown in the figure. The direction of the induced current as observed by an observer on the other side of the loop will be