The endpoints of a segment are (10, 0) and (20, 0) how do you know it is a horizontal segment

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?

(if f(x)=4x^2 and g(x)=x+1, find (f o g)(x)

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?