The molar mass of the compound was found to be 30.069 g/mol. what is the molecular formula?

It will be hard to found the compound molecular weight just by the weight. I can think 2 kind of atom for this configuration.

First, it was NO or nitric oxide. It molecular weight is 16+14 = 30. But if you search the exact weight is 30.01 g/mol

Second, it was (CH3) 2 or ethane. The molecular weight is 2*12 + 6*1 = 30. But if you search the exact weight is 30.07 g/mol. So it more likely to be ethane.