Analysis: the propulsion rate before square meters and square centimeters is 10000, so 45 square meters =45× 10000=450000 square centimeters.

2230 minutes =3 hours and 50 minutes

Analysis: the hourly progress rate is 60, and you can borrow 10 minutes to 230 minutes, that is, 240 minutes is 4 hours, and 230 minutes is 3 hours and 50 minutes.

3. 10 at 5: 00 -4: 20 =0: 50.

Analysis: 1 hour is 60 minutes, and 5: 00 -4: 20 minutes can be converted into 1 hour 10 -20 minutes, that is, (60+ 10)-20 = 50 minutes, available, 5.

4600 cm =60 decimeters =6 meters

Analysis: the penetration rate between centimeter and decimeter is 10, between decimeter and meter is 10, and between centimeter and meter is 100. So, 600 cm =60 decimeters =6 meters.

5. 237 days =5688 hours =34 1280 minutes =20476800 seconds.

1, and the hourly rate is 24237 days =237×24=5688 hours.

2. The forward speed of hours and minutes is 60. To sum up, 237 days =5 688 hours =5 688×60=34 1280 minutes.

3. The propulsion rate per second is 60, and the following conclusions can be drawn: 237 days =34 1280 minutes =34 1280×60=20476800 seconds.

6. One cubic kilometer = 10 18 cubic millimeter

Analysis: The propulsive rates of cubic kilometer and cubic meter are 10 9, cubic meter and cubic decimeter are 10 3, cubic decimeter and cubic centimeter are 10 3, cubic centimeter and cubic millimeter are 10 3, 1 cubic kilometer = 650.