Which two observations can be made in relation to population growth over centuries? the solution of 3tan2x ? 1 = 0 if x is in the first quadrant is °. the solution of 3tan2x ? 1 = 0 if x is in the second quadrant is °.

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?