E[cX] = c * E[X] where c is a constant
E[XY] = E[X] * E[Y] where X and Y are independent variables
measuring the spread of data: mean absolute deviation and mean squared deviation
Var[X + Y] = Var[X] + Var[Y] where X and Y are independent variables
deriving the E[X] and Var[X] for the iid variables
an equation for the population variance using the sample mean, and the sample size
regression coefficient of y on x