At Nick's school, 25% of the 72 sixth-grade students wear either glasses or contact lenses. How many sixth-grade students wear either glasses or contact lenses?

Add, subtract, multiply, or divide as indicated. list any restrictions for the variable(s) and simplify the answers when possible. 1) x-2 / x+5 + 3x / 2x-1 2) x+6 / x-6 - x^2 / x+6 3) x+9 / x-4 + x+2 / x^2-11x+28 4) x / x^2-64 + 11 / 2x^2+11x-40 5) 5 / x + 11 / x-3 - x-4 / x^2+2x-15

What is the measure of angle x? 37° 82° x°

In chemistry, n molecules of an ideal gas have pressure, volume, and tempersture that stand inthe following relation, where r is constant. solve the equation for n, the number of molecules. pv=nrt