1 m = 10 decimeter =100 cm =1000 mm.

1 decimeter =10cm =100mm

1 cm = 10/0mm

One kilometer = 1000 meter

Tertiary weight unit:

Grams, kilograms, tons,

1 kg =1000g

1 ton = 1000 kg

The third grade area unit:

Square meters, square decimeters, square centimeters,

1 m2 = 100 m2

1 square decimeter = 100 square centimeter

Third grade time unit formula:

1 year = 12 months

Da Yue: 3 1 day

Abortion: 30 days

February: 28 or 29 days

Average year: 365 days: 52 weeks 1 day.

Leap year: 366 days: 52 weeks and 2 days.

1 week =7 days

1 day =24 hours

1 hour =60 minutes

1 min =60 seconds