Assuming this is multiple choice, the answer would be "niche". An organism's niche is where that certain organism fits into an ecosystem, or what their part to play is.
<span>In grafting, the plant with desired root system is called the <u>rootstock</u>, and the portion of the plant with the buds is called the <u>scion</u>.
The grafting is a horticultural technique in which parts from two or more plants are joined together to grow as a one single plant.
Rootstock is the plant selected for its roots because it can provide different properties, such as fruit size, or because it is resistant to drought or diseases.
Scion is the plant selected for its leaves, flowers, fruits or stems.
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Since Lithium has one valence electron that means it needs to lose it to form a stable structure. That means it's valence is equal to one. Oxygen has six atoms, in order to form a stable octet structure it needs to accept 2 electrons, therefore it's valence is 2.
Therefore two Lithium atoms bond with one oxygen atom to form Li2O
84.798 is the mass number