What is the slope of the line

(note i put the graph in so plz )the graph shows the amount of water that remains in a barrel after it begins to leak. the variable x represents the number of days that have passed since the barrel was filled, and y represents the number of gallons of water that remain in the barrel. what is the slope of the line

Laura read 1/8 of a comic book in 2 days. she reads the same number of pages every day. what part of the book does she read in a week

Aschool had an election where the candidates received votes in the ratio 1: 2: 3. if the winning candidate received 210 votes, how many total people voted in the election?