Open the combination lock using the old combination. Remove the u-bar from the lock body so it's in the Unlock position. Use a screwdriver to open the anti-dust cover on the back of the combination lock. Align the old combination numbers to the guide points.
A base pair (bp) is a unit consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix, and contribute to the folded structure of both DNA and RNA.
At that particular spot, C would pair with G, forming a double helix with the same sequence as its original (i.e., before the wobble occurred), but A would pair with T, forming a new DNA molecule with an A-T pair in place of the original C-G pair. This type of mutation is known as a base, or base-pair, substitution.