Question

be it ordained ordered by the united states in congress assembled, that the powers and duty of the secretary at war shall be as follows... to examine into the present state of the war department, the... present state of the troops, ordnance explosives, arms, ammunition, clothing, and supplies of the troops of these states, and report the same to congress. according to this passage, what is the main duty of the secretary at war? to stay informed about the military and its supplies to command the us army in battle if the president is unable to to fight any enemy congress chooses to examine the relationship of the united states to other countries

Explanation:

The passage states the Secretary at War must examine the state of the war - department, troops, supplies etc. and report to Congress. This implies staying informed about the military and its supplies.

Answer:

to stay informed about the military and its supplies