classification based on modulus of elasticity

Question

Classification Based on Modulus of Elasticity:

Young's modulus is resolute by conducting bending test. On this basis timber is classified as following:

Group A: E = 12.5 kN/mm²

Group B: E = 9.8 kN/mm2 to 12.5 kN/mm²

Group C: E = 5.6 kN/mm2 to 9.8 kN/mm².