A student wants to estimate the height of a tree from ground level. He measures the length of its shadow as 10 m and the angle from the top of the shadow on the ground to the top of the tree as 60°. What is the height of the tree based on these measurements?

Consider a file currently consisting of 200 blocks. assume that the file control block (and the index block in the case of indexed allocation) is already in memory. calculate how many disk i/o operations are required for contiguous, linked, and indexed (single-level) allocation strategies, for each of the conditions listed below. in the contiguous-allocation case, assume that there is not room to grow at the beginning but there is room to grow at the end. also assume that the block information to be added is stored in memory.