Ineed to know how to solve it and the anwser

Which statements regarding the diagram are true? check all that apply.

Iq scores for adults age 20 to 34 years are normally distributed according to n(120, 20). in what range does the middle 68% of people in this group score on the test?

What are the solutions of the equation? 5z^2 + 9z - 2 = 0 a. 1, -2 b. 1, 2 c. 1/5, -2 d. 1/5, 2