Answer:
See below.
Step-by-step explanation:
So we know that a gym membership costs $25 plus $14 each month.
In other words, the one-time cost is $25 and there will be a cost of $14 each month.
We can write this as:

Where f(x) equals the total cost given the number of months x.
For 6 months, the total cost will be:

1) Mean
The mean is given by the sum of the data divided by the number of data (4, in this case):

2) Standard deviation
The standard deviation is given by:

where

is the mean, that we already found at point 1), and N=4. Substituting data, we have:

Answer:
Range: 12
Step-by-step explanation:
65, 66, 67, 68, 71, 73, 74, 77, 77, 77
Formula:
Range: highest value - lowest value = final answer
Range: 77 - 65 = 12
From 17 x 17. to simplify, (1/2(17)(17) x tan A)
No. This is not random sampling as the students chose are not chosen at random. Random sampling would be something done where each sample has equal probability of being chosen. Clearly this is not random sampling.