The number of balloons that can be completely filled by emptying the helium cylinder is 406.
The number of balloons to be filled by the cylinder is calculated by using general gas equation as shown below;
[tex]\frac{P_1V_1}{T_1} =n( \frac{P_2V_2}{T_2})[/tex]
where;
[tex]\frac{850 \times 28}{301.5} =n( \frac{14.88 \times 3.75}{287})\\\\78.94 = 0.194n\\\\n = 406[/tex]
Thus, the number of balloons that can be completely filled by emptying the helium cylinder is 406.
Learn more about gas equation here: https://brainly.com/question/25736513
#SPJ1