the measurements are 7.76, 7.76, 7.85, 7.79, 7.75

we need to find the Mean and the Variance to find the Standard Deviation:

Mean = (7.76 + 7.76 + 7.85 + 7.79 + 7.75)/5

Mean = 7.782

to calculate the Variance, we need to take each difference, square it, and then average the result:

Variance = ((7.782-7.76)^2 + (7.782-7.76)^2 + (7.782-7.85)^2 + (7.782-7.79)^2 + (7.782-7.75)^2)/5

Variance = 0.001336

the Standard Deviation is just the square root of Variance:

Standard Deviation = 0.001336^0.5

Standard Deviation = 0.036551338