Find the number of moles in 8.75 x 1022 molecules of water.

0.66y = 0.9x + 0.48 if y has a value of 108.45 what is the value of x?

An empty fuel tank can still contain and therefore can be even more dangerous than one full of liquid fuel.

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?