Suppose that 1 mL of TEL is added to 1,000 mL of heptane. Based on Experiment 2, one would predict that the octane number of the TEL/heptane mixture would be:
a. higher than the octane number of pure heptane, but lower than 115.
b. higher than the octane number of pure heptane, and higher than 115.
c. lower than the octane number of pure heptane, but higber than 115.
d. lower than octane number of pure heptane, and lower than 115.