A student took measurements of the mass of an object using the same balance. The data obtained were the following: 1.383 g, 1,387 g, 1.389 g and 1.382 g. With these data calculate the average mass and...

A student took measurements of the mass of an object using the same balance. The data obtained were the following: 1.383 g, 1,387 g, 1.389 g and 1.382 g. With these data calculate the average mass and the standard deviation. If the true value for the mass of that object is 1.488 g, what is the percent error?