Answer:
That is, mechanical waves cannot travel through a vacuum. This feature of mechanical waves is often demonstrated in a Physics class. A ringing bell is placed in a jar and air inside the jar is evacuated. Once air is removed from the jar, the sound of the ringing bell can no longer be heard.
REM, it is the deepest sleep and will send you deep within the mind
Answer:
The answer is D
Explanation:
I'm too lz to explain everything.
sorry.
Humans need a digestive system to do cellular respiration, which produces energy used for growth and movement.
Plants do not need one as they make their own energy through photosynthesis. The process produces glucose, which is a form of energy for the plants.
Fe and S are both reactants: they react with each other to give a different compound.
FeS is the product of the reaction: it was formed or produced as result of the reaction of Fe and S.
Answer:
Fe: reactant
S: reactant
FeS: product