What source is most likely to provide a historian with credible information about a historical figure ?

At the casablanca conference, allied leaders signed an agreement to share military technology decided to launch an invasion of southern france agreed to accept only the unconditional surrender of the axis powers agreed to form a scientific team to create the atomic bomb

Many blacks moved from the south to northern cities during world war li looking for employment. after the war, a number of them lost their jobs. why did this happen?

The political cartoon below was drawn by thomas nast in 1871: a political cartoon shows a heavy set man with a long nose and a beard in a suit and vest. he is smoking a cigar and has a menacing expression. he leans against a large box that says, in counting there is strength. on top of that box is a smaller container labeled, the ballot. dialogue under the cartoon reads, thats whats the matter. boss tweed, as long as i count the votes, what are you going to do about it? say? public domain what issue does this cartoon address?