Simplify 0.00021 * 0.000028 and Express your answer in standard form(scientific notation)

The surface area (sa) of a cube with a as the length of each of its sides is given by the formula . if the surface area is known, how can you rewrite the formula to find its side?

Multiply. write your answer in simplest form. 3/8 x 5/7

:24% of students in a class are girls. if there are less than 30 students in this class, how many students are there? how many girls are there?