Answer:
Hope this helps :D
Explanation:
Metal: Aluminum and Copper
Non-Metal: Hydrogen and Flourine
Acid: Sulfuric Acid and Phosphoric Acid
Alkali Metals: Hydrogen and Lithium
Compounds: Water and Carbon Dioxide
Elements: Carbon and Oxygen
There are 4 significant figures! Start counting after the first non-zero digit :)
Hope this helps.
there are valence electrons 3 in group 10.
As one element .because po4 is phosphate for e.g.: NaPO4
