CAN SOMEONE HELP ME OUT PLEASE AND THANK YOU

Find the missing variable for a parallelogram: a = latex: 28in^2 28 i n 2 h = b = 6.3 in (1in=2.54cm)

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?

What is a correct first step in solving the inequality-4(3-5x)> -6x+9