Answer:
The answer is A. $421.29
Step-by-step explanation:
Just keep finding 19% of the numbers next, and you add that all up and you get the answer.
250 x 19%=47.5. (250+47.5)=> 297.5x19%= 56.525. (297.5+56.525) =>354.025x19%=67.26475
354.025+67.26475=> 421.28975, which can round up to 421.29.
40 minutes*7 days of the week= 280 minutes a week. So, 320-280= 40 minutes left over. 40:320= 1:8. You were correct!
Answer: 
Step-by-step explanation:
The confidence interval for population mean is given by :-

Given : Sample size :
, which is a large sample , so we apply z-test .
Sample mean : 
Standard deviation : 
Significance level : 
Critical value : 
Now, a confidence interval at the 95% level of confidence will be :-

I'm not sure but I think it's 5