(1) Use and adjustment of the balance: put the balance on the horizontal workbench, put the travel code on the zero scale line of the balance, and adjust the balance nut of the balance to make the balance beam horizontally balanced;

(2) Weigh the glass and residual brine on the left panel of the balance. When the balance is rebalanced, the weight and travel code position are shown in the figure, and the mass m2 of the glass and residual brine is 50 g+5 g+3.2 g = 58.2 g;

The mass of brine in the measuring cylinder is m = m1-m2 =130.2g-58.2g = 72g;

The dividing value of the measuring cylinder is 2mL, and the volume of brine in the measuring cylinder is V=60mL=60cm3.

Saline water density: ρ = MV = 72g, 60cm3 =1.2g/cm3 =1.2x103kg/m3.

So the answer is: (1) ACB; (2) See the table below. Glass and salt water.

Mass m 1/g mass m2/g of residual brine in glass and measuring cylinder.

Quality of brine in m/g measuring cylinder

Saline volume V/cm3 Saline density

ρ/(kg？ m-3) 130.258 260 1.2× 103