So you can use
$21.95 + $.19x = $18.95 + $.21x
Unit Rate:
6 plants in 1 square yard
Square yard for every 100 grass seeds
8 seeds per square foot
2 plants per square foot
Rate:
25 trees per 25 yards
4 acres for 800 plants
The only formula that can be used to describe the sequence is definitely the third one

. So count like that

and so on. You can check others by yourself to check if I'm right or not.
Answer:
b
Step-by-step explanation:
Which table of ordered pairs represents a proportional relationship