Assume you inhale in about 6 L of air per minute how much nitrogen do you breathe in one minute

This means he inhale 4.68 L of Nitrogen in 1 minute.

Explanation:

Air constitute 78 percent of nitrogen. That means to get the amount available in 6 L we need to find 78 % of nitrogen in 6 L.

78 % of 6L can be computed as follows:

78/100 * 6 = 468/100 = 4.68 L

This means 4.68 L of Nitrogen is present in 6 L of air.

This means he inhale 4.68 L of Nitrogen in 1 minute.

Since He inhale 6 L of air in 1 minute and 6 L of air contains 4.68 L of Nitrogen that means he inhales 4.68 L of Nitrogen in 1 minute.

78.09% or 4.6854 L of nitrogen in one minute. 78.09% of the Earth's atmosphere is composed of nitrogen, so it would make sense this proportion would hold true as you are breathing it in.