While scuba diving, you have injured yourself and must signal the boat on the surface for help. You have five laser pointers, each emitting light of a different color: red, orange, yellow, green, and blue. When you shine the yellow light up toward the boat, the beam makes such a small angle with the surface that all the light is reflected back into the water.

(a) If you are not able to move closer to the boat, which color or colors of light might you try?

(b) Are these other lights likely to be successful in penetrating the surface at that point?