Answer : 4. "584.7 billion dollars"
Explanation :

The country's foreign exchange reserves fell for the fifth consecutive week by $ 2.2 billion to 584.7 billion in the week ending October 06 due to decline in foreign currency assets, gold, Special Drawing Rights (SDR) and reserves with the International Monetary Fund (IMF). Dollar remained the same, whereas in the previous week it had decreased by 3.8 billion to 586.9 billion dollars.