Suppose that an i-phone producer produces 300 i-phones a week. Initially the price of i-phone is $200 and the demand function for i-phone is: x1=20+(m/(10*p1)), where x1 is the amount of i-phones demanded and p1 is the price of i-phone . Calculate the substitution effect, ordinary income effect and endowment income effect of an increase in p1 by 20% on the the amount of i-phones demanded