G A = {hR, Si : R, S are regular expressions such that L(R) ⊆ L(S)}. Present a proof to show that A is decidable. You may find the proof of Theorem 4.5 instructive when presenting your proof to this problem.

The path traveled by a bottlenose dolphin as it jumps out of water is modeled by the equation y=-0.4+3x, where t is the height above water and x is the horizontal distance in feet. if a beam of light is shone upward at an angle modeled by the equation x+y=10, at what height from the waters surface will the beam of light hit the dolphin