Answer:
[tex]m_a=22.5\ kg[/tex] is the mass of air.
[tex]m_w=810\ kg[/tex] is the mass of water.
Explanation:
Given:
We know:
[tex]\rm density=\frac{mass}{volume}[/tex]
So, mass of air in the room :
[tex]\rho_a=\frac{m_a}{V_a}[/tex]
[tex]1.25=\frac{m_a}{18}[/tex]
[tex]m_a=22.5\ kg[/tex]
Mass of water in the tub:
[tex]\rho_w=\frac{m_w}{V_w}[/tex]
[tex]1000=\frac{m_w}{0.81}[/tex]
[tex]m_w=810\ kg[/tex]