Which expression is exactly equivalent to 5a + 3b + 4 + 7a + 9 ? Expression 1: 8a + 11b + 9
Expression 2: 12a + 3b + 13
Expression 3: 5a + 10b + 13
Expression 4: 14a + 10b + 4

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