In Mexico City, only 55-60% of the population owns a telephone. The number drops to less than 50% in Guadalajara and Monterey, and 35% or lower in other cities. This will complicate the task of market researchers hoping to use a telephone survey to obtain a of the Mexican population.

Probability sampling.

Explanation:

Probability Sampling is a sampling method whereby sample from a bigger population are chosen through the use of probability theory. For a participant to be chosen as a probability sample, he or she must be chosen through a random selection. The most vital requirement in probability sampling is that everyone should have an equal chance of being selected e.g. if there is a population of 200 people, everyone involved will have an odd of 1 in 200 to be selected.

Probability sampling provides the best chance to get a sample that truly represents the population.

answer; societal marketing;

answer the amount a seller is paid minus the cost of production;