Two aqueous sulfuric acid solutions containing 20.0 wt% H₂SO₄ (SG = 1.139) and 60.0 wt% H₂SO₄ (SG = 1.498) are mixed to form a 4.00 molar solution (SG = 1.213).

(a) Calculate the mass fraction of sulfuric acid in the product solution.

(b) Taking 100 kg of the 20% feed solution as a basis, draw and label a flowchart of this process, labeling both masses and volumes, and do the degree-of-freedom analysis. Calculate the feed ratio (liters 20% solution/liter 60% solution).

(c) What feed rate of the 60% solution (L/h) would be required to produce 1250kg/h of the product?