It would be option A, -413
Answer:
For this case we want to test if in IT companies more than 20% of employees prefer to use Skype rather than a mobile phone (alternative hypothesis) and the complement would be the the null hypothesis. So then the system of hypothesis are:
Null hypothesis: 
Alternative hypothesis: 
And for this case we should use a righ tail test based on the alternative hypothesis.
Step-by-step explanation:
Previous concepts
A hypothesis is defined as "a speculation or theory based on insufficient evidence that lends itself to further testing and experimentation. With further testing, a hypothesis can usually be proven true or false".
The null hypothesis is defined as "a hypothesis that says there is no statistical significance between the two variables in the hypothesis. It is the hypothesis that the researcher is trying to disprove".
The alternative hypothesis is "just the inverse, or opposite, of the null hypothesis. It is the hypothesis that researcher is trying to prove".
Solution to the problem
For this case we want to test if in IT companies more than 20% of employees prefer to use Skype rather than a mobile phone (alternative hypothesis) and the complement would be the the null hypothesis. So then the system of hypothesis are:
Null hypothesis: 
Alternative hypothesis: 
And for this case we should use a righ tail test based on the alternative hypothesis.
Answer:
We put the value of the x in the formula

f(6)=

Step-by-step explanation:
Than solve equation.
Answer:
189
Step-by-step explanation:
You take 63% make it a decimal by dividing it by 100 and then you multiply it with 300. 300*.63=189.
root means square velocity of one mole of a monoatomic gas having molar mas*s m(M) is Urms. The relation between average kinetic energy (e)of the gas and Urms is Urms=M2E
StarrySoul please check it...