What is the molar mass of 2.4g of oxygen

Phosphorous acid, h3po3(aq) , is a diprotic oxyacid that is an important compound in industry and agriculture. the values of phosphorous acid are 1.30 6.70 calculate the ph for each of the given points in the titration of 50.0 ml of 1.5 m h3po3(aq) with 1.5 m koh(aq) .

What human activity increases beach erosion?

If anyone would be able to me out with these three questions it would be these are from the chem 2202 course.