Use the appropriate Newman projection for 2-methylbutane about the C2-C3 bond to write the most stable conformer for 2-methylbutane.

Newman projection of 2-methylbutane with substituents around the C2-C3 bond.

Newman projection of 2-methylbutane with both methyl groups staggered.

Newman projection of 2-methylbutane with one methyl group eclipsed.

Newman projection of 2-methylbutane with two methyl groups eclipsed.