The answer for this multiple choice question is C
Answer:
carbon dioxide
Explanation:
because we breath in oxygen and breath out Carbon
Answer:
3,964 years.
Explanation:
- It is known that the decay of a radioactive isotope isotope obeys first order kinetics.
- Half-life time is the time needed for the reactants to be in its half concentration.
- If reactant has initial concentration [A₀], after half-life time its concentration will be ([A₀]/2).
- Also, it is clear that in first order decay the half-life time is independent of the initial concentration.
- The half-life of the element is 5,730 years.
- For, first order reactions:
<em>k = ln(2)/(t1/2) = 0.693/(t1/2).</em>
Where, k is the rate constant of the reaction.
t1/2 is the half-life of the reaction.
∴ k =0.693/(t1/2) = 0.693/(5,730 years) = 1.21 x 10⁻⁴ year⁻¹.
- Also, we have the integral law of first order reaction:
<em>kt = ln([A₀]/[A]),</em>
where, k is the rate constant of the reaction (k = 1.21 x 10⁻⁴ year⁻¹).
t is the time of the reaction (t = ??? year).
[A₀] is the initial concentration of the sample ([A₀] = 100%).
[A] is the remaining concentration of the sample ([A] = 61.9%).
∴ t = (1/k) ln([A₀]/[A]) = (1/1.21 x 10⁻⁴ year⁻¹) ln(100%/61.9%) = 3,964 years.
Answer:
There is no bar graph attached to this question, however, the question can be answered based on the information given in the question.
The answer is A) average level of happiness
Explanation:
In an experiment, the dependent variable is the variable which is measured by the experimenter. It is the variable that responds to changes made to another variable called independent variable.
In the case of this question, it can be determined, even without the bar graph, that the experiment entails how candy allowance affects a child's happiness. Hence, the candy allowance is changed to influence or cause a response in the child's happiness, which is then measured. Therefore, the AVERAGE LEVEL OF HAPPINESS is the dependent variable.
Correct answer: B. Paleozoic. I took the test and it was right.
