Answer:

Step-by-step explanation:

Here is the link to the graph. You can scale it and tweak it.
https://www.desmos.com/calculator/mawkflj9ws
Hope this helped!
Part A:
There are 8 possible outcomes.
HHH
TTT
HTH
THT
TTH
HHT
THH
HTT
Part B:
There is 2 outcomes that consist of all head or all tails.
Part C:
You would expect about 6 students to get all head or all tails.
Hope this helps c:
A. we use the z statistic to solve this problem
z = (x – u) / s
We calculate the value of the sample mean u and standard deviation
s:
u = $30 * 304 = $9120
s = $21 * 304 = $6384
z = (9,600 – 9120) / 6384
z = 0.075
From the normal tables using right tailed test,
P = 0.47
B. At worst 11% means P = 0.11, so the z value at this is
z = -1.23
-1.23 = (x – 9120) / 6384
x = 1267.68