1. The problem statement, all variables and given/known data A) Under optimum conditions, the smallest black dot that can be seen subtends an angle of 2.3 x 10-6 rad. If a dot is viewed at a distant of 0.25 m, the near point of a normal adult, what is the smallest diameter it can have and still be seen? B) The maximum resolution is obtained when the image falls on the fovea centralis. At 10° away from this region, the acuity is 10 times poorer. What is the minimum size spot that can be seen at that angle under these conditions? 2. Relevant equations Pf = 1/xf + 1/D Pf = person's far point, 1/xf = distance a person sees an object, D = image distance Pn = 1/xn + 1/D Pn person's near point, 1/xn - distance a person sees an object, D = image distance A = Pn - Pf A = power of accommodation sin θ = 1.22 (λ/d)-power of acuity equation λ = wavelength, d = diameter 3. The attempt at a solution I've puzzled over this problem. I'm not sure what the relevant equation would be unless I'm missing one. Any help is appreciated.