How do u solve 3and 1 half minus 1 and 1 half

1) you deposit $2,500 in an account that earns 4% simple interest. how much do you earn in eight years?

Is triangle jkl congruent to triangle rst? if so, what is the scale factor?

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?