check my work??

Kim is studying the sale of a particular brand of cereals from the year 2000 to 2010. She writes the following function to model the sale of the cereal S(t), in million dollars, after t years:

S(t) = t2 + 7t + 69

Part A: What does the y-intercept of the graph of the function represent? (4 points)

Part B: What is the reasonable domain of the graph of the function? (3 points)

Part C: What is the average rate of change of the sale of the cereal from the first year to the fourth year? Show your work.

Question

check my work??

Kim is studying the sale of a particular brand of cereals from the year 2000 to 2010. She writes the following function to model the sale of the cereal S(t), in million dollars, after t years:

S(t) = t2 + 7t + 69

Part A: What does the y-intercept of the graph of the function represent? (4 points)

Part B: What is the reasonable domain of the graph of the function? (3 points)

Part C: What is the average rate of change of the sale of the cereal from the first year to the fourth year? Show your work.

anonymous · Answer

Part a. what does the y-intercept of the graph of the function represent?
the sale of the cereal at the start

Part B: What is the reasonable domain of the graph of the function?  
The domain is the time from 2000 to 2010
Part C: What is the average rate of change of the sale of the cereal from the first year to the fourth year? Show your work
t^2 + 7t + 69 
4^2 + 7(4) + 69 
16 + 28 + 69

anonymous · Answer

@tester97 

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@fighter23 
@lovelyharmonics 
@sloppyjo

anonymous · Answer

that looks about right

anonymous · Answer

@bangbang559 do you think you could help me with my problem?