For a linear triangular element with (xi, yi) as the coordinates of the ith node of the element the area=10units, the value of ∑γi from the standard relation αi+βiX+γiY=(2/3)*Area where X=∑xi, Y=∑yi is ___

(a) 0

(b) 10

(c) 20

(d) 30

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This interesting question is from Boundary Value Problems in section Single Variable Problems of Finite Element Method