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Your answer is correct. But they don't call it Confidence Interval. This is just 95% of a normally distributed population. Which is as you said mean +/- 2 standard deviations, 95% Confidence Interval of the mean on the other hand is calculated by this formula
mean +/- 2 Z scores X SD/N
Actually, the formula for a 95% CI is

mean + or - [Z score x sd/sqrt(N)]...and Z is almost 2 (95% confidence Z score = 1.96), you dont have to multiple Z score by two...and dont forget the square root in the denominator. :)
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