Under most biological conditions, however, histidine is considered to be a triprotic acid. This is due to the pKa of the being .A. nitrogen in the imidazole ring possessing a hydrogen but no charge; much lower than the pH values normally found in a cellB. nitrogen in the imidazole ring possessing a hydrogen but no charge; much higher than the pH values normally found in a cellC. carboxylic acid; much lower than the pH values normally found in a cellD. carboxylic acid; much higher than the pH values normally found in a cell

the answer to your question is b

answer: zinc is the substance which has a volume of 1.38 .

density is defined as the mass of an object per unit volume.

it can be calculated by dividing mass of a substance by its volume i.e.

si unit of density is kg per cubic meter and cgs unit of the same is gram per cubic centimeter.

now from the given data volume can be calculated by the formula .

hence, the volume of aluminium will be = which comes out to be 1.703 .

similarly, volume of zinc, chromium, and nickel will be 1.378 , 0.869 , and 0.356 respectively.