Do you measure the air quality in a completely inflated ball with a balance? Talk about plans

The basic methods and ideas are as follows:

Let the inside of the ball communicate with the outside air first, and weigh the mass m 1.

Blow the air in the big ball and weigh the mass m2.

Then let out the gas in the ball, collect and measure its volume under normal pressure, V 1,

Measure the diameter d of the ball and calculate its volume V2, (V2=( 1/6)πD? )?

(m2-m1) (v1+v2)/v1is the mass of air in the inflatable ball.