Final answer:
The range of diopters for spectacle lenses needed after the LASIK procedure is from 8.55 D to 9.45 D. The patient was nearsighted before the procedure since the power of the eye was reduced to correct the vision, which is the usual treatment for myopia.
Step-by-step explanation:
If a laser vision correction reshapes the cornea of a myopic (nearsighted) patient and reduces the power of his eye by 9.00 diopters (D) with an uncertainty of ±5.0%, the range of diopters for spectacle lenses the patient may need after the LASIK procedure can be calculated as follows:
The uncertainty in correction is 5.0% of 9.00 D, which equals 0.45 D. Therefore, the range of correction would be from 9.00 D - 0.45 D to 9.00 D + 0.45 D, giving us a range from 8.55 D to 9.45 D.
Regarding the question of whether the person was nearsighted or farsighted before the procedure, we can deduce that the person was nearsighted because the procedure involved decreasing the power of the eye.
Myopia or nearsightedness is a condition where a person can see close objects clearly, but distant objects appear blurry. This is typically corrected by reducing the diopter strength of corrective lenses or in this case, surgically reducing the power of the cornea.