AP Biology Equations and Formulas Review Sheet 1. Grasshoppers in Madagascar show variation in their back-leg length. Given the following data, determine the standard deviation and standard error for this data. Length in cm: 2.0, 2.2, 2.2, 2.1, 2.0, 2.4 and 2.5 2. Initial mass of pumpkin cores was measured in grams. What is the average initial mass