Answer: 
Step-by-step explanation:
The confidence interval for population mean is given by :-

Given : Sample mean :
hours
Standard deviation
hours
Sample size : n=90, which is a large sample(n<30), so we use z-test.
Significance level: 
Critical value : 
Then , the confidence interval for population mean will be :-

Hence, the 90% confidence interval for the mean life
of all light bulbs of this type. is 
I do not know what this is but don’t cry
Unfortunately, you have not shared any of the fractions in question. 412, 48, 42 and 410 are all "integer" or "whole" numbers. Please share the entire question.
Example: 48 2/3 can be re-written with a repeating decimal:
48 2/3 = 48.666666666 .....
First one is 33y^3-22y^2-27y+18
Second one is -3a^4-20a^2 x^2+7x^4
I hope this helps you :)
Mark Brainliest please.
Answer : The ladder will reach 20.6 feet.
Explanation:
Refer the image attached for explanation