The graph shows the proportional relationship between the number of sodas you buy and the cost of the sodas. Explain what the constant of proportionality (k), means in the context of the situation.
A: 4 sodas cost $6
B: One soda cost $7
C: One soda cost $2
D: One soda cost $4
E: 3 sodas cost $1
One soda costs $2. As you can see, which each soda you buy, X and Y go up by two. The relationship of X and Y is x=2y, with X being sodas and Y being dollars
