The hexagon below is divided into 6 identical triangles, in the area of the shaded parallelogram is 42 in what is the area of the hexagon?

What is the number 321,000,000 in scientific notation? also what is the number? ?

Marla bought a book for $12.95, a binder for $3.49, and a backpack for $44.99. the sales tax rate is 6%. find the amount of tax and the total she paid for these items

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?