can someone help me. if which one is correct or if neither is correct?

VL Compute for Price Elasticity of Demand (Set A), Income Elasticity of Demand (Set B), Cross Elasticity of Demand (Set C) Price Quantity 100 10 200 15 A. = (Q2 - Q1) / (P2 - P1) = 15- 10/200 -100 = 5 / 100 = 0.05 H B. = (Q2 / Q1) / (P2 / P1) = (15 / 10) / (200 / 100) = 1.5/2 = 0.75 C. = 02 - 01 P2 - P1 02 + 01 P2 + P1 15 - 10 200 - 100 15 + 10 200 + 100 = (5/ 25) / (100 / 300) - 0.2/0.4 -0.6