Question

the secretary at war
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's duty is to examine the state of the war - department, troops, supplies etc. and report to Congress. This means staying informed about the military and its supplies.

Answer:

to stay informed about the military and its supplies