The Quantity of Coffee Demanded, Q^d, Depends on the Price

The quantity of coffee demanded, Q^d, depends on the price of coffee, P_c, and the price of tea, P_T. The quantity of coffee supplied, Q^s, depends on the price of coffee, P_c, and the price of electricity, P_E , according to the following equation:
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Q^d = 17 - 2P_c + 10P_T
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Q^s = 2 + 3P_c - 5P_E
a.If the price of tea is $1.00 and the price of electricity is $0.50, what are the equilibrium price and quantity of coffee?
b.What is/are the endogenous variable(s) in this model?
c.What is/are the exogenous variable(s) in this model?​