Match List-I with List-II:
\[
\begin{array}{|l|l|}
\hline
\textbf{List-I (Vaccines)} & \textbf{List-II (Their respective contents)} \\
\hline
A. \ \text{Typhoid vaccine} & I. \ \text{Killed rickettsia} \\
B. \ \text{Typhus vaccine} & II. \ \text{Killed bacteria} \\
C. \ \text{Measles vaccine} & III. \ \text{Attenuated viruses} \\
D. \ \text{Smallpox vaccine} & IV. \ \text{Killed viruses} \\
\hline
\end{array}
\]
If 0.01 mol of $\mathrm{P_4O_{10}}$ is removed from 0.1 mol, then the remaining molecules of $\mathrm{P_4O_{10}}$ will be:
An element has two isotopes having atomic masses 10 and 15 u, respectively. If the percent abundance of lighter isotopes is 80%, then the average atomic mass of the element is: