From the diagram you can see that for all

This means that function is constant on the interval 
Answer: correct choice is C.
1.9
Do sin54 * 2.3
Because sin54 = x/2.3
First, multiply both sides by 88, because you can divide 88 by 22. That final would be 3k*88/22 = -13. Simplified, that would be 12k = -13. Divide both sides by 12, making the final answer k = -12/13, or in decimal form 1.08333...