Tom has two pieces of wood to build a birdhouse one piece is 3/4 yards long the other piece is 4/8 yard long. tom says both pieces of wood are the same length explain his error

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed