Which answer accurately describes the difference between speed and velocity?
a. speed requires distance. velocity requires direction.
b. speed is the result of a change in direction. velocity is the result of a change in acceleration.
c. gravity affects speed. gravity does not affect acceleration.
dspeed measures a change in inertia. inertia remains the same in velocity.

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.