How are pull factors calculated?

Group of answer choices

a$.$

The pull factor, for a certain type of retail good or service, is the trade area capture estimate for that retail good or service divided by the municipal population.

b$.$

The pull factor, for a certain type of retail good or service, is the Reilly$$s law estimate for that retail good or service divided by the municipal population.

c$.$

The pull factor, for a certain type of retail good or service, is the trade area capture estimate for the retail good or service divided by the municipal per capita income

d$.$

All of the above