Complete Question
The complete question is shown on the first uploaded image
Answer:
The number of student that have heard the announcement after 4 hours is
Explanation:
From the question we are told that
Now at time t = 0 f(t) = 300 this because at the time the announcement was made the number of student present was
so
=>
So the above equation becomes
Now at the given time t = 2hr
So
So the equation is now
Now at t = 4 hrs we have that