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.
I think it A because Cyanobacteria absorb co2 from the atmosphere and then release oxygen To the atmosphere
The answer is hydrogen and oxygen
Explanation:
Cancer occurs in dividing cells only because genetic materials divide into two equal portions during division. This process may be interrupted by carcinogenes or mutagenes to make mutate cells and then render them as cancer cells. In the brain, the cells are differentiated and there is no chance to start division, then how can cancer be found in the brain.
The organs represented in the image are the Brain, nerve, and spinal cords that monitor and react to changes in the body and its environment.
<h3>What are Organs?</h3>
Organs may be defined as an assemblage of tissues that structurally construct an operational unit specialized to accomplish a distinct operation and functions in the body of a living organism.
The nerves function in sending and receiving signals to the brain from external stimuli. They give the perception of feeling pain, relaxation, stress, etc to the brain according to the situations.
The complete question is as follows:
The picture shows an organ system in the human body.
Brain, Nerve, and spinal cord.
What do these organs do in the human body?
- They filter pathogens and dead cells out of lymph before it returns to the blood.
- They monitor and react to changes in the body and its environment.
- They release hormones that control the activities of cells and organs.
- They identify and destroy things that are foreign or harmful to the body.
Therefore, the correct option for this question is B, i.e. They monitor and react to changes in the body and its environment.
To learn more about Organs, refer to the link:
brainly.com/question/1126526
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