2. W<5
4. D<6 (or equal to)
Answer:
(34, 48)
Step-by-step explanation:
According to the Empirical Rule, 95% of normally distributed data lie within two standard deviations of the mean. That, in turn, means 95% of the data in this problem lie within 2(3.5 min), or 7 min, of the mean:
41 - 7 < mean < 41 + 7, or
34 < mean < 48, or simply (34, 48)
Answer: 3rd one
Rearrange the original equation so it fits the model of : ax^2+bx+c=0
Then use the quadratic formula to find all possible answers.
