Hello
A. At this age power usually does not change
B. There is no significant difference between 0.5and 0.75...This difference could be due to interindividual variability
C. Regarding 6/9 vision, information provided by you is incomplete... Kindly share your case file and your glasses prescription so that I may guide you better
Regards
Answered2017-11-09 04:44:00
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