After two half-lives or 60 years, 7.5 g of the element will be left.
<u>Explanation:</u>
<u>Half-life:</u>
- In simple words, Half-life can be defined as the amount of time needed for a quantity to fall to half its value as contained at the beginning of the time period.
- In this problem the half-life of the element is thirty years, then after thirty years half of the sample would have decayed and half would be left as it is.
- After thirty years (The first half-life ) 30 /2 = 15 g declines and 15 g remains disappeared.
- And after another sixty years (The two half-lives) 15 /2 = 7.5 g declines and 7.5 g remains disappeared.
- After two half-lives or 60 years, 7.5 g of the element will be left.
The word that goes on to the gap is "cells"
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Answer:
<h2>The source rock is the rock that contains the kerogen that the oil and gas forms from. The reservoir rock is the porous, permeable Rock layer or layers that hold the oil and gas. This migration occurs because oil and gas are less than than water.</h2>
It is called PANGEA THE SUPERCONTINENT
Answer
D) colons should be used after independent clauses that come before lists.
Explanation: