Australia is one of the major exporters of coal as one of its resources. However, there are many other producers of coal in the world. Suppose the price of coal is set in an internationally competitive market and all the coal produced are homogenous.

(a)Due to a major reduction in demand because of environmental concerns, the demand for coal decreased significantly. However, at the same time some mines across the world are closed due to production issues. Explain how would the market equilibrium price and quantity for this product change internationally?