Very simple. You just use the vectors as normal numbers, and multiply the coordinates with 2 and 4 like this:
2*u = 2* (2,4) = (4,8)
4*w = 4* (-1,3) = (-4,12)
(4,8) - (-4,12) = (8,-4)
So the vector has the coordinates (8,-4)
Answer: 
Step-by-step explanation:
The confidence interval estimate for the population mean is given by :-
, where
is the sample mean and ME is the margin of error.
Given : Sample mean: 
The margin of error for a 98% confidence interval estimate for the population mean using the Student's t-distribution : 
Now, the confidence interval estimate for the population mean will be :-

Hence, the 98% confidence interval estimate for the population mean using the Student's t-distribution = 
Answer: 18 ft per second
Step-by-step explanation: 36 divided by 2