I.2 30 5.2 3 36

Two. 15 15 630

Three. 1，3.4-0.5x=2

0.5x= 1.4

x=0.7

2、2.5x= 12.5

x=5

3, 3 times =2.8

x=0.7

Four. 1, 360* 16= 12x x=480 (pieces)

2. Area of each face: 2 16/6=36 Side length: root number 36=6 Volume: 6*6*(6+3)=324.

3. Length: 0.5x=2.5 x=5 Width: 0.8y=6.4 y=8.

Suppose store b has x kilograms of rice. 350+120 = 2 (x-120)+70, x=320 (kg)