With the increased usage of cell phone services, what has happened to the price elasticity of demand for land-line telephone services?
(a) it has become more income elastic.
(b) it has become more price inelastic.
(c) it has become more price elastic.
(d) the absolute value of the price elasticity coefficient has probably gone down.

The correct answer is c) "It has become more price elastic"

Explanation:

With the increased usage of cell phone services, the demand for land-line telephone services decreased.

If the demand won´t change, this is inelastic. If the demand changes, it is elastic.

example:

If the price of the cellphones increses, I would use more the land line telephone. Elastic

if the price of cellphones decreased, I won´t use the land line telephone (actually ocurring) Elastic

if the price of salt decreases, I will consume the same amount per month and I wouldn´t need more product. Inelastic

Could you translate the question to English? I study Spanish and I think you are saying that a gas sample has a volume of 0.5 litres and 750mm hg of pressure then calculate the volume of gas if the temperature is 40 degrees and the pressure is 1026 atm but I am not sure I am just assuming that is your question so your answer would be to use the equation of V x 1/P as it is inversely proportional. Hope I helped