Respuesta :

Answer:

b. y = 1000x

Constant of proportionality = 1,000

Step-by-step explanation:

The equation that represents a proportional relationship between variable x and y usually takes the following form, y = kx.

Where,

k = constant of proportionality.

From the three given equations, the only equation that takes the form is b. y = 1000x.

The constant of proportionality (k) of the equation = 1,000.