Which one does not belong 3: 4, 9: 12, 12: 15, 12: 16 and why

Need solving this second acceleration problem.

How does a low unemployment rate affect a nation's economy? a. the nation has a higher number of productive resources. b. the nation can spend more money on for unemployed people. c. the nation can save money by paying lower salaries to a large workforce. reset

What are the solutions of the equation? z^2 + 11z + 24 = 0 a. 8, -3 b. 8, 3 c. -8, -3 d. -8, 3