Consider a multilevel computer in which all levels are different. Each level has instructions that are m times as powerful as those of the level below it; that is, one level r instructions that are m times as powerful as those of the level below it; that is, one level r instruction can do the work of m level r-1 instructions. If a level-1 program requires k seconds to run, how long would equivalent programs take at levels 2, 3, and 4, assuming n level r instrucions are required to interpret a single r+1 instruction?