=6250/25

=250 (ton)

(2)420/7*6

=60x6

=360 (Ben)

(3)2x3. 14x9x32

=6.28x9x32

=56.52x32

= 1808.64 (cubic centimeter)

2 liters

(4) The square of1x 3.14x (2x3.65438+25. 12 of 04) is x 1.8.

= 3. 14x 16x 1.8。

= 50.24x 1.8/3

=30. 144 (m3)

2 cm = 0.02 m

30. 144/0.02/20

= 1507.2/20

=275.36 meters

≈275 meters

5.( 1) Use four factors of 8 to form a set of proportions (8:4=2: 1).

(2) Write two ratios with the ratio of 0.4 and make up the ratio (3.2: 8 = 2: 5).