What is the value of the expression 8 to the 3 power​

Use the frequency distribution, which shows the number of american voters (in millions) according to age, to find the probability that a voter chosen at random is in the 18 to 20 years old age range. ages frequency 18 to 20 5.9 21 to 24 7.7 25 to 34 20.4 35 to 44 25.1 45 to 64 54.4 65 and over 27.7 the probability that a voter chosen at random is in the 18 to 20 years old age range is nothing. (round to three decimal places as needed.)

When using the linear combination metho e linear combination method to solve a system of linear equations, the four options are:

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?