What??? what language is this?
Lithium-7 is the most common isotope of lithium.
The most obvious answer for this would be a product i think.
A) all mechanical waves need a medium to travel through.
This is true because mechanical waves move in a wave like manner at the atomic level. This is why an table vibrates when you put a speaker on top of it .
The appearance of the protist differ from that of the onion sample due to the presence of motile structures.
<h3>What is a Protist?</h3>
This is an eukaryote which could be unicellular or multicellular and examples include protozoa etc.
The major difference between a protist and onion sample is that protists have motile structures such as flagella, cilia etc while plant cells such as onions don't have.
Read more about Protist here brainly.com/question/2169979
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