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.
A fossil would from through mineral replacement by replacing the existing material of the animals bones with minerals, to become petrified. The Minerals will keep the fossil preserved longer.
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Answer:
1) To form a multicellular organism, a zygote must divide into 16 cells which produces ball structure called a morula. After that, morula is converted into a structure called blastula.
2) Adult stem cells are responsible for the maintenance of tissues and repair the damage tissues in the body. It is also called somatic stem tissue. It increase in number through cell division.
Answer:
A) NaCl will be exported from the red blood cells by facilitated diffusion.
