Answer: 
Explanation: 1 gram is equal to 1000 Milligrams so

Since you go straight across its just multiplication so 0.00200x1000=200mg
To answer it in scientific notation it should just be
mg
Answer:
2510
Explanation:
Since there are 10 milimetres in 1 centimetre, 1 cm = 10mm
There are 10 times as many milimetres as centimetres.
251cm X 10 = mm
251cm = 2510mm