Answer:
Null hypothesis: 
Alternative hypothesis: 
The alternative hypothesis for this case is that at least one mean is different from the others. 
And the best method for this case is an ANOVA test. 
Step-by-step explanation:
For this case we wnat to test if all the mean length of all face-to-face meetings and the mean length of all Zoom meetings are the same. So then the system of hypothesis are:
Null hypothesis: 
Alternative hypothesis: 
The alternative hypothesis for this case is that at least one mean is different from the others. 
And the best method for this case is an ANOVA test. 
 
        
             
        
        
        
Answer:
sin θ = 
Step-by-step explanation:
Given that,
cos θ = 
From the trigonometric functions,
cos θ = 
⇒ adjacent =  , and the hypotenuse = 3
, and the hypotenuse = 3
Let the opposite side be represented by x, applying the Pythagoras theorem we have;
 =
 =  +
 + 
 =
 =  +
 + 
9 = 3 + 
 = 9 - 3
 = 9 - 3
    = 6
x = 
Thus, opposite side = 
So that,
sin θ = 
         = 
Therefore,
sin θ = 
 
        
             
        
        
        
Answer:
B
Step-by-step explanation:
.45y+.3(0) = 3.6
y=8
8 does not equal 12