Answer:

Step-by-step explanation:

The answer for your question is 45 cm long
Answer: 75 students.
Step-by-step explanation:
In the data set we have a total of 10 + 8 + 7 + 5 = 30 students.
of those, 10 want to go to the park, the percentage is:
(10/30)*100% = 33.3%
Then, out of the 225, we can expect that a 33.3% (or 0.333 in decimal form) want to go to the park, this is:
N = 225*0.333% = 74.925
We can roud it up, and get N = 75
So Sally can expect that 75 students want to go to the park
First, note that

is always positive (except for x=0), so

must be always negative.
Thus, the only plausible graphs are 1 and 3 since they are below the x-axis.
Now,

and

are only defined for x≥0, because only for these x'es we can take the square root.
Note that the third graph has domain (-infinity, 0], so it is not the right one, while 1 is ok.
Answer: first graph