Competition: Stinkbugs; Parasitism: geometrid moths Competition: geometrid moths; Commensalism: stinkbugs; Mutualism: guava and eucalyptus trees
Competition: stinkbugs and geometrid moths; Commensalism: guava and eucalyptus trees
Parasitism: geometrid Moths; Commensalism: stinkbugs; Mutualism: guava and eucalyptus trees

i'd say that the moon rock is about 2.2 billion years old.

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds