pls explain.thanks

Next Problem (8 points) A bag contains two red balls, one green ball, and four yellow balls, Balls are drawn from the bag one at a time at random without replacement until a yellow bail has been d Let random variable R represent the number of red balls drawn, Complete the probability distribution function for R in the table below, then find ET.R) . Enter your answers numbers or fractions in lowest terms. R Pr(R) ER