Which best describes the purpose of a control sample? to have more quantitative data to analyze at the end of the experiment
to have more qualitative data to analyze at the end of the experiment
to compare its results to those of a well-known scientist
to compare its results to those with the experimental sample

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.