Please use an explanation in this!

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.)

Standard deviation of 19,29,21,22,23

(30 points). the population of a city is 45,000 and decreases 2% each year. if the trend continues, what will the population be aer 15 yrs