1. Positive numbers are: 10, +3.8, three quarters, 20.8, +40, half and+three eighths.

Negative numbers are: -4, -2.5, -0.25, -8, -35.2, -6.

2.-5 degrees Celsius 0-15-10 minutes +20 degrees

3. BC

4. The number of minus 24 minus1217 8.6-12/9

5.+ 1kg-2kg-0.5kg-50kg, so don't write+1.5kg-3kg-1.5kg.

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