Question

Magnesium is
Select all that apply

dangerous to look at when it burns
found in fresh water lakes
used in photography, fireworks, and flares
a compound made up of two elements

Answer 1

dangerous to look at when it burns. ** yes
found in freshwater lakes. As Mg is found in certain rocks eg dolomite, it is possible in those regions, and is also necessary for chlorophyll production. Most fresh water lakes grow green plants, so yes.
used in photography, fireworks, and flares.** yes
a compound made up of two separate elements. ** no it is just one element.