Can someone answer? i’m litterally so confused

Carter drank 15.75 gallons of water in 4 weeks. he drank the same amount of water each day.a. estimate how many gallons he drank in one day.b. estimate how many gallons he drank in one week.c. about how many days altogether will it take him to drink 20 gallons?

Apatient is to be given 35 milligrams of demerol every 4 hours. you have demerol 50 milligrams/milliliter in stock. how many milliliters should be given per dose?

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.