Answer:
The number of days are independent and the total number of minutes are dependent.
The required model for the situation is 
The table is shown below:
Step-by-step explanation:
Consider the provided information.
Joshua spends 25 minutes of each day reading. Let d be the number of days that he reads, and let m represent the total minutes of reading.
We need to determine which variable is independent and which is dependent.
Here, the number of days are independent and the total number of minutes are dependent.
If he spends 25 minutes each day. So the total number of minutes in d days are:

The required model for the situation is 
Now make the table which showing the number of minutes spent reading over 7 days.
Substitute the value of d from 1 to 7 in 
Number of days(D) Minutes(M)
1 25
2 50
3 75
4 100
5 125
6 150
7 175
Answer:
Option C) 0.2358
Step-by-step explanation:
We are given the following data set:
0.23105, 0.4725, 0.8765, 0.4865, 0.5326, 0.7976
Formula:
where
are data points,
is the mean and n is the number of observations.


Sum of squares of differences = 0.1122752556 + 0.008765640625 + 0.09633264063 + 0.006340140625 + 0.001123925625 + 0.05358067562 = 0.2784182787

Thus, the standard deviation for given data is
Option C) 0.2358