The value p (price) at which the supply of a crop equals the demand for that crop is called the equilibrium price. The equation for the supply of soy beans is S = 0.3p + 3 The equation for the demand of soybeans is D = -0.5p + 9. Determine the equilibrium price. A) $6.50 B) $6.75 C) $7.00 D) $7.50