A=F/m
a=(3000000)/(20000)
a=15 m/s^2
The average speed of light is 186,000 mph
Explanation:
Sodium is a chemical element with the symbol Na (from Latin "natrium") and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. ... The free metal does not occur in nature, and must be prepared from compounds.
From that particular list:
Mica (A), Quartz (B), and Copper (D) are minerals.
Steam (C) isn't.