Root Beer Float with pudding

1 (8 ounce) carton reduced-fat whipped topping, thawed and divided 3/4 cup root beer, cold diet 1/2 cup nonfat milk 1 (1 2/3 ounce) box sugar-free instant[...]

1 (1 ounce) package jello sugar-free instant vanilla pudding mix 2/3 cup nonfat dry milk powder 1 1/2 cups diet root beer 1/2 cup Cool Whip Lite 1 In a medium[...]