Answer:
4 gallons
Step-by-step explanation: for each gallon she used one
So the following is the answer of the following question in your problem and please do not post to many question in just one posting.
#1 The 98% confidence interval for the mean hours is between 6 and 50.
#2 The smallest margin of error between the two is southern florida with 1.8% margin of error.
Answer:
For the first 30 minutes, we will have a line with a given steepness, this will represent the 30 minutes riding at a fast pace.
Then he stops for 20 minutes, we will represent this with a constant line.
Then he again moves for another 30 minutes, but with a slower pace than in the first 30 minutes, then this line will be less steep than the first line.
A sketch of this situation can be seen below.
Answer:
5.6
Step-by-step explanation:

![\sf \left[\begin{array}{cc}\sf 4&\sf 6\\ \sf 5 &\sf 8 \\ \sf 3 &\sf -2\end{array}\right]-\left[\begin{array}{cc}\sf 2&\sf 3\\ \sf 1 &\sf 4 \\ \sf -5&\sf3\end{array}\right]](https://tex.z-dn.net/?f=%5Csf%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Csf%204%26%5Csf%206%5C%5C%20%5Csf%205%20%26%5Csf%208%20%5C%5C%20%5Csf%203%20%26%5Csf%20-2%5Cend%7Barray%7D%5Cright%5D-%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Csf%202%26%5Csf%203%5C%5C%20%5Csf%201%20%26%5Csf%204%20%5C%5C%20%5Csf%20-5%26%5Csf3%5Cend%7Barray%7D%5Cright%5D)
Just substract corresponding terms
![\\ \sf\longmapsto \left[\begin{array}{cc}\sf 2 &\sf 3\\ \sf 4&\sf4\\ \sf 8&\sf -5\end{array}\right]](https://tex.z-dn.net/?f=%5C%5C%20%5Csf%5Clongmapsto%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D%5Csf%202%20%26%5Csf%203%5C%5C%20%5Csf%204%26%5Csf4%5C%5C%20%5Csf%208%26%5Csf%20-5%5Cend%7Barray%7D%5Cright%5D)
Option B