A sample of size n is selected from a large lot of shear drill bits. Suppose that a proportion p₁ contains exactly one defect and a proportion p₂ contains more than one defect (with p_{1 + p2} < 1 ). The cost of replacing or repairing the defective drill bits is C = 4Y₁ + Y₂ , where Y1 denotes the number of bits with one defect and Y2 denotes the number with two or more defects. Find the expected value of C.