Please please help me asnswer it correctly and fastly

The global oil market has been affected in the recent years by many factors that induces the global price to fall. This consequence is vital for the budget of the oil dependent countries. After the huge decrease on oil price in 2016, many traders and analysts believe that oil markets are still not immune to many problems and the oil price will tend to fall again.

The main factor and problems toward a fall of the oil price started in 2015 but considering that people and oil companies do not tend to react immediately to the change of oil price, the total consumption and production of oil did not get any surprised changes in the short- run.

The main factor that caused the drop on the oil price is the OPEC failure. The member countries of OPEC did not agree to stabilize the oil markets, since the organization decided against cutting production at a 2014 meeting in Vienna.

It is estimated that if OPEC does not cut production, the result is a further oversupply of oil, causing a pressure on crude oil prices for the long term.

On the other hand, we have faced a slight decline of the demand. The economies of Europe and developing countries are weakening, and at the same time, vehicles are becoming more efficient, which has caused the demand for fuel to lag. Moreover, many countries are relying on alternative resources than oil, which has further decreased the oil demand.

After reading the information above, answer the following questions:

1. a) Explain the main reasons that caused a fall of the oil price started in 2015.

b. Is the elasticity of demand and supply for oil in the short-run elastic or inelastic? Explain why? 

c. Illustrate  graph the consequences caused by an oversupply (high increase) on supply and a slight decline (small decrease) of demand. 

-What will happen with the price of oil, will increase or decrease?  

-What about the total quantity of oil production, will increase or decrease?