Answer:
5 mm,3 cm,20 cm,1.5 m
Explanation:
First convert them all to the same unit for example i converted them all to cm, so 5 mm is 0.5 cm and 1.5 m is 150 cm and now you have them all in cm now put them in order from smallest to largest so final answer is 5mm,3cm,20cm,1.5m (NOTE):When writing final answer write with units given not with the units you converted to to