I believe the correct answer from the choices listed above is option D. Catalysts lower the activation energy of a chemical reaction. It <span>is a substance which speeds up a reaction, but is chemically unchanged at the end of the reaction. It provides another pathway for the reaction to occur.</span>
Seasickness. The symptoms of carbon monoxide poisoning mimic the symptoms of seasickness.
I believe the correct answer from the choices listed above is option B. A double-replacement reaction happens when atoms in one compound switch places with atoms in another compound. <span> It is a type of chemical </span>reaction<span> where two compounds </span>react<span>, and the positive ions (cation) and the negative ions (anion) of the two reactants switch places. Hope this answers the question.</span>
Answer:
In 4 years the carbon monoxide level reach 7.8 parts per million.
Explanation:
The average daily level of carbon monoxide in the air is given by :
parts per million..[1]
The population of the region after t years is modeled by the formula :
...[2]
If level of carbon monoxide level reach 7.8 parts per million in t years.
Using [1] to calculate value of x.
c(x)= 7.8 parts per million
c(x) = 0.5x + 2 parts per million
7.8 parts per million = (0.5x + 2 ) parts per million
Solving for x , we get ;
x = 11.6
Using [2] to calculate value of t.:
x(t) = 11.6

Solving for 't' we get ;
t = 4 years
In 4 years the carbon monoxide level reach 7.8 parts per million.