Someone please helppp

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?

Identify all the cases where non-probability sampling is used when attempting to study the characteristics of a large city. studies on every subject in the population divide a population in groups and obtain a sample studies with a limited amount of time demonstrate existing traits in a population studies with the nth person selected

As a self-employed seamstress, you know that it takes 7 yards of material to make 3 jackets. you bought 15 yards of material to make 7 jackets. did you buy enough material? if not, how much were you over or under?