1. The problem statement, all variables and given/known data A child is standing at the edge of a straight highway watching her grandparents' car driving away at a constant 22.4 m/s. The air is perfectly clear and steady, and after 8.3 minutes the car's two taillights (654 nm) appear to merge into one. Assuming the diameter of the child's pupils is 4.76 mm, calculate the width of the car. 2. Relevant equations Θ = 1.22 λ/D 3. The attempt at a solution I solved for theta by plugging in the wavelength and diameter (came out to be 1.676 e -4 rad), then found the distance from the car using distance = time x speed = 11155.2m and multiplied that by the angle to find what I thought would be half the width of the car, and multiplied that by two to get an answer of 3.74m-- however, that's apparently incorrect and I'm not sure what I did wrong. Any help with be really appreciated. Thank you!