<h2>Answer:</h2>
C) The scientist made an identification
<h2>Explanation:</h2>
The fingerprint is a very certain method for identifying a person, because all human beings have got unique fingerprints. Forensic laboratories have database of all citizens in the area. Hence an identification is done by the results matched with the database information. The two main categories of fingerprint matching techniques are minutiae-based matching and pattern matching and both are them are present in the given database.
A 20 L sample of the gas contains 8.3 mol N₂.
According to <em>Avogadro’s Law,</em> if <em>p</em> and <em>T</em> are constant
<em>V</em>₂/<em>V</em>₁ = <em>n</em>₂/<em>n</em>₁
<em>n</em>₂ = <em>n</em>₁ × <em>V</em>₂/<em>V</em>₁
___________
<em>n</em>₁ = 0.5 mol; <em>V</em>₁ = 1.2 L
<em>n</em>₂ = ?; <em>V</em>₂ = 20 L
∴<em>n</em>₂ = 0.5 mol × (20 L/1.2 L) = 8.3 mol
The charge would be -2 because there are 2 more electrons than protons, and electrons have a negative charge.
