Add the product of 5 and 6 with the product of 3 and 7

Because of your favorite lemonade it is $3.84 for 3 gallons. write this as an unit rate

Which of the following are independent events? a) knowing that it is going to rain tomorrow, and bringing an umbrella to schoolb) knowing that you have to get up early tomorrow, and going to bed before 9 p.mc) knowing that it is going to rain tomorrow, and going to bed before 9 p.md) knowing that you have a test in school tomorrow, and studying thw night before

David pays a 20% income tax on his $2,100 salary. how many dollars is the tax? show work