Question

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Maria created a graph of B(t), the temperature over time. For the interval between t = 3 and t = 7, the average rate of change in her graph of B(t) is 8. Which statement must be true?
a) The temperature was 8 degrees higher when t = 7 than when t = 3.
b) The temperature was 8 times higher when t = 7 than when t = 3.
c) The temperature was 32 degrees higher when t = 7 than when t = 3.
d) The temperature was 2 degrees higher when t = 7 than when t = 3.