Answer:
The average velocity of the airplane for this trip is 1684.21 km/h
Explanation:
Average velocity is the rate of change of displacement with time. That is,
Average velocity = 
= Δx / Δt = 
Now we will calculate the time taken by the airplane for the first motion before it encounters a wind.
From,
Velocity = 
Time = 
Therefore, Time = 
Time = 2.1h
This is the time taken before the airplane encounters a wind.
Hence, t1 = 2.1h
Now, For the time taken by the airplane when it encounters a wind
Also from,
Velocity =
Time =
Therefore, Time = 
Time = 1.625h
Hence, t2 = 1.625h
Now, to calculate the average velocity
Average velocity =
x1= 2100, x2= 1300, t1= 2.1h and t2= 1.625h
Hence, Average velocity = 
Average velocity = 1684.21 km/h
Answer:
7.28 mol Na2SO4
Explanation:
Since it is already in moles, all we have to do is use a molar ratio
A molar ratio is the proportions of reactants and products using the balanced equation. When writing a mole ratio, the given information must cross out with the right thing.
7.28 mol H2SO4 * 1 mol Na2SO4/1 H2SO4 = 7.28 mol Na2SO4
*notice how the H2SO4 crosses out
The question is incomplete as it does not have the options which are:
(1) receiving antibiotic injections after surgery
(2) choosing a well-balanced diet and following it throughout life
(3) being vaccinated against chicken pox
(4) receiving hormones contained in mothers milk while nursing
Answer:
Being vaccinated against chicken pox
Explanation:
Vaccination is the procedure of giving the disease-causing germs which could be virus and bacteria in their dead or weakened state, some toxin, some proteins or some other molecules called a vaccine.
The benefit of providing vaccination is that the provided pathogen acts as an antigen and triggers the proactive immune response against the pathogen which helps in eradicating the main pathogen that has invaded the body. The vaccination is used to treat the disease like chickenpox, measles, tetanus and many others.
Thus, the selected option is correct.
Answer: Option (b) is the correct answer.
Explanation:
The given chemical reaction shows that hydrogen cyanide acid has been added to water which results in the formation of hydronium ion and cyanide ion.
Also, when we add a base like sodium hydroxide (NaOH) to HCN then it will help in accepting a proton (
) from hydrogen cyanide. As a result, formation of 
anion will be rapid and easy.
This will make the system not to do any extra work. So, amount of work done by system will decrease.
Thus, we can conclude that out of the given options, add solid NaOH to the reaction (assume no volume change) will decrease the amount of work the system could perform.
