Standard deviation is calculated by the square root of the variance. Now, how do we solve the variance? The variance is the <span>average of the </span>squared differences from the Mean. Calculating the variance, we can obtain a standard deviation of <span>3.74. Therefore, the correct answer is option A.</span>
I think it's 79.50 square units. there three triangles in the quadrilateral shape above with the areas given so add the areas together to get the answer