Please help now its important

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) .

The volume of helium in a blimp is 6.28 x 10^9 millimeters. the density of helium in the blimp is .1786 kilogram/meter^3. find the mass of the helium in the blimp.

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?