I don't know what I'm doing lmk asap

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

Fran has 7 sheets of paper for a coloring project. if she only uses 1/3of a sheet of paper per draing how many drawings can ahe make?

While on a train trip, marsha noticed that there were 35 people in her train car. after the next stop, there were only 21 people in her car. if p represents the percent decrease in the number of people in marsha's train car, what is p?