its only showing "help i will mark brainliest"..?
I'm not really sure for 3, but for 4, it is not free of influence since they are waiting for a horror movie.
What would be better for question 4 is to ask people at the lobby or something before they are entering a movie theater so the results aren't "contaminated".
Answer:
17.088
Step-by-step explanation:
Question:
Complete question for this is to find the equation for this and may be the graph.
Explanation:
As for the oscillation motion, initially peak is occurring hence it will be a cosine function with peak value of 3(cm).
To calculate time period, the whole cycle should be 360°
i.e.
cos (Xπ.t) = cos (360)
as the cycle completes at 1.2 sec hence by putting t=1.2, answer should be 360.
i.e.
X*180*t=360
X*180*1.2=360
X=5/3
So, the required equation is

Graph for this equation is attached here with this answer.
In graph,
x-axis: t=0 ~ t=1.2
y-axis: f(x)=-4 ~ f(x)=4