The flywheel on a steam engine rotates 60 revolutions every 15 seconds what is the flywheel rate of revolution per second

Multiplying an even number of negative numbers gives an answer that is choose from:

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

Select the lengths in centimeters that would form a right triangle