The table below shows the amounts of lemon juice and sugar used in each container of lemonade. The ratio of lemon juice to sugar is 1:r, where r is the unit rate. Use the table to determine r. (4 points) Lemon Juice (cup) Sugar (cup)
one-half 1
2 4
3 6
a
2

b
one-half

c
1

d
two-thirds