A. Andrew Johnson was president from 1865 when Lincoln was assassinated to 1859, where he lost reelection to Ulysses S. Grant.
B to out compete rival businesses as if they lowered their prices more than their competitors, they could drag in more customers
To calculate the population density, you will divide the population by the size of the area. Thus, Population Density = Number of People/Land Area. The unit of land area should be square miles or square kilometers. You can use square feet or meters if you are finding the density of a smallish space.