Economic questions. 14. The supply of MiB in a country is 100 billion yuan; among them, the net currency is 20 billion yuan, and the current deposit is 800 million yuan. It is known that the reserve currency of a country is 28 billion yuan.

(A) If there are bank runs in a certain country, the livelihood of the population will decrease and the average amount of currency held will increase from 20 billion to 24 billion. What is the final amount of prepared currency in this country?
(B) If the central bank of this country raises the deposit reserve ratio from 0.1 to 0.2, but assuming other conditions remain unchanged, the net currency remains unchanged at 20 billion yuan. What is the final amount of reserve currency?
(C) Please compare the size of the currency multiplier in the above two cases.