1.75 0,8 5. 1900-0,04 2. 2,5.300 6. 3500 0,009 3. 0,28.250 7. 0,005 4600 4. 140-1,75 8. 2500 12,75

It looks like you've provided a series of mathematical expressions or calculations. I'll interpret these as operations and calculate them one by one.

1. 1.75 × 0.8 = 1.4

2. 5 × (1900 - 0.04) = 5 × 1899.96 = 9499.8

3. 2.5 × 300 = 750

4. 140 - 1.75 = 138.25

5. 3500 × 0.009 = 31.5

6. 0.28 × 250 = 70

7. 0.005 × 4600 = 23

8. 2500 × 12.75 = 31875

If these calculations are not what you were looking for, please provide additional context or specify what you would like to achieve!