Answer of Part A is 243 Lunches
Answer of Part B is 850.50$
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:
f(x)
Step-by-step explanation:
the function f(x) crosses the y-axis higher than either of the other functions, therefore it has the largest y-intercept
Answer:
$540
Step-by-step explanation:
2460 = 4x + k
1920 = 3x + k
k is our student service fee, which we represent as a constant
subtracting the equations to remove k and isolate x, our cost per course
540 = x