Which table shows a proportional relationship between x and y?

x 1 2 3 6
y 1.5 3 6 9

x 3 5 7 8
y 1.5 2.5 3 4.5

x 2 4 5 6
y 6 12 18 21

x 1 3 4 5
y 50 150 200 250

The first week samantha learned to read braille, she could read 10 words per minute. in the second week she increased her speed by 20%. in the third week she increased her speed again by another 25%. how many words could she read per minute by the third week? hurry and tell me!