Answer:
second table (see the attached figure)
Explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
or
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
Verify each table
First table
Let
x ----> the weight in lb
y ----> the price in dollars
For x=1.5, y=3.50
Find the value of the constant of proportionality k
---->

For x=2, y=7
---->

The values of k are different
therefore
This table not represent a proportional relationship between weight and price
Second table
Let
x ----> the weight in g
y ----> the price in dollars
For x=1.5, y=0.90
Find the value of the constant of proportionality k
---->

For x=8, y=4.80
---->

The values of k are equal
therefore
This table represent a proportional relationship between weight and price
Third table
Let
x ----> the weight in kg
y ----> the price in dollars
For x=2, y=0.75
Find the value of the constant of proportionality k
---->

For x=5, y=3.75
---->

The values of k are different
therefore
This table not represent a proportional relationship between weight and price
Fourth table
Let
x ----> the weight in oz
y ----> the price in dollars
For x=2 oz, y=4
Find the value of the constant of proportionality k
---->

For x=4 lb, y=8
convert to oz
1 lb=16 oz
4 lb=64 oz
---->

The values of k are different
therefore
This table not represent a proportional relationship between weight and price