How do estimate the difference of mixed numbers

If the class was going to get a class pet and 5 picked fish and 7 pick bird and 8 picked rabbits have many students were in the

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?

Sara goes on a slingshot ride in an amusement park. she is strapped into a spherical ball that has a radius 3*10^2 of centimeters. what is the volume of air in the spherical ball? use this formula: volume of a sphere=4/3pi,r^3 , where r is the sphere’s radius.