Question

Convert 2.5 days to seconds. Convert 35 km to millimeters. Convert 43 cm to kilometers. Convert 22 mg to kilograms. Convert 671 kg to micrograms.

Answer 1

1 day = 24 hours = 1440 minutes = 86 400 seconds
so 2.5 days = 216 000 seconds.

1 km = 1000 m = 100 000 cm
so 35 km = 3 500 000 cm

The reverse is true here
1 cm =  1   m =      1       km
           100       100 000
so 43 cm is     43      km
                   100 000

1 kg = 1 000 g = 1 000 000 000 μg
so 671 kg = 671 000 000 000 μg