A mixture of water ( = 1000 kg/m3) and oil ( = 800 kg/m3) is flowing through

Question:

A mixture of water (ρ = 1000 kg/m3) and oil (ρ = 800 kg/m3) is flowing through a tube of diameter 2 cm with a velocity of 4 m/s. The mass flow rate is measured to be 1.068 kg/s. Determine
(a) The density (ρ) of the liquid mixture
(b) The percentage of oil in the mixture by mass. Assume liquids to be incompressible.