False, it states that matter can be nether created nor destroyed
Answer:- 12 km = 12000 m
Solution:- It's a metric unit conversion where we are asked to convert 12 km to m where km stands for kilometer and m stands for meter.
In metric conversions, kilo means 1000.
So, 1 km = 1000 m
It means, we multiply the given km by 1000 to get the answer in m as:

= 12000 m
Hence, 12 km = 12000 m.
Nitrogen=2, Hydrogen=8, Carbon=1, Oxygen=3
Hydrogen=4, Carbon=2, Oxygen=2
Iron=1, Nitrogen=2, Oxygen=6
Both mass and weight are measured by using scales.