Can someone help with these Metric System Conversions

I know this should be easy, but I'm really having trouble. I'm not understanding how many zeros are needed when converting to micro or nano. I mean are u suppose to have all six zeros for mirco or all nine for nano? For example:

5000nm = _________micrometers = __________mm

1.5g= 1500mg = 1500000mircograms: not sure if that's right

55nm=__________micrometers =____________km

0.25l=__________ml =__________microliters

651m= 65100cm =__________nm: not sure if the first part is right

8578ml= 8.578l =__________microliters: not sure about the first part

1.75km= 175000mm =__________nm: not sure about first part

0.09053mm= .00009053m = 00.009053cm: not sure if it's right

93.61kg= 93610000mg = 93610g: not sure if it's right

If u can't help me with all of them, that's fine, but just need help with some, thxs in advance.

If you have a tiny unit, you need more of them to get an equal value.

For example, there are 100 cents in a dollar.

If you have 5,000,000 cents, you really have "only" 50,000 dollars, and you only have 50 "thousands"
You remove zeros as you move from the tiny unit to the bigger unit.

In the metric system, most ratios are one thousand, meaning that you work with groups of three zeros.

5000 nm = 5 micrometre = 0.005 mm = 0.000005 m = 0.000000005 km

going the other way, you add zeros (usually in groups of 3)

1.5 g = 1,500 mg = 1,500,000 μm = 1,500,000,000 ng = 1,500,000,000,000 pg = and so on

The ones to watch for are the ones that do not have a ratio of 1,000

1,000 mm = 100 cm = 10 dm = 1 m

1,000,000 mm = 100,000 cm = 10,000 dm = 1,000 m = 100 Dam = 10 Hm = 1 km

Luckily the "Deca" is very rarely used. Traditionally, its symbol used Da (with a capital D) but some people use da, so that a decametre becomes a dam.