Match the words in List-I with those in List-II.
\[ \begin{array}{|c|l|c|l|} \hline \text{List-I} & & \text{List-II} & \\ \hline (a) & \text{One who studies the formation of the Earth} & (i) & \text{Psephologist} \\ \hline (b) & \text{One who gazes at the stars in the sky} & (ii) & \text{Geologist} \\ \hline (c) & \text{One who studies the occurrence of volcanoes and earthquakes} & (iii) & \text{Seismologist} \\ \hline (d) & \text{One who predicts the outcome of elections} & (iv) & \text{Astronomer} \\ \hline \end{array} \]
A sum of Rs. 800 amounts to Rs. 920 in 3 years at simple interest. What would be the amount, if the interest rate is increased by 3%?
In what ratio must water be mixed with milk to gain 20% by selling the mixture at cost price?