Answer:
2 point capital gain
Step-by-step explanation:
Every municipal bond that is purchased at premium is subject to straight line depreciation, whether the premium be trading premium or original issue premium.
Here the premium is 5 points = 105 - 100
Which shall be amortised over its useful life of 10 years.
Thus, for each year 1/2 point is amortised without allowing any tax deduction.
Thus, after 4 years total amortisation =

Thus, value at end of year 4 = 105 - 2 = 103 basis point.
Further the selling amount = 105 basis point.
Thus, 105 - 103 = 2 basis point shall be taxable.