Which of the following is a major source of protein?

Which one of the following items gives its correct total number?

Which of the following is not an ore of magnesium?

If $(a \times b)^2 + (a \cdot b)^2 = 144$ and $|a| = 4$,then $|b| = $

Which of the following is the strongest conjugate base?

Solution $X$ contains $Na_2CO_3$ and $NaHCO_3$. $20 \ mL$ of $X$ when titrated using methyl orange indicator consumed $60 \ mL$ of $0.1 \ M$ $HCl$ solution. In another experiment,$20 \ mL$ of $X$ solution when titrated using phenolphthalein consumed $20 \ mL$ of $0.1 \ M$ $HCl$ solution. The concentrations (in $mol \ L^{-1}$) of $Na_2CO_3$ and $NaHCO_3$ in $X$ are respectively: