For example, your pet could be an A+, A or A-. Some pets will evolve only once, and others have two stages of evolution. For first stage evolution, the letter grade will determine which level a pet evolves in the following window: Levels 12 to 18. For second stage evolution, the letter grade will determine which level a pet evolves in the following window: Levels 24 to 32. There are exceptions to these rules but this will give you a general idea as to when your pets will evolve.
THE THIRTEENTH AMENDMENT. (freed the slaves) The Emancipation Proclamation was meant to free the slaves in the Confederate States, but the Confederate government did not recognize the Union President freeing their slaves. The Thirteenth Amendment, however, freed the slaves everywhere in the United States.
As a correction, the Emancipation Proclamation, enacted by Lincoln in 1863, only freed the slaves in those states that were rebelling. Because the Union only controlled some small portions of the south at the time, only a small number of slaves were immediately freed. Slavery everywhere in the US wasn't abolished until the ratification of the 13th amendment in 1865, and there were still some slaves in the northern states who weren't freed until then.