“Anchoring earth” refers to the earth under which the roots of a tree are held firmly, thereby providing strength and nourishment to it. “Earth cave” again refers to the earth. The poet calls it so, as the roots, which are the most sensitive part of the tree, stay hidden securely under the earth.
In Fig. 9.26, A, B, C and D are four points on a circle. AC and BD intersect at a point E such that ∠ BEC = 130° and ∠ ECD = 20°. Find ∠ BAC.