Write a function to evaluate the string containing the prefix expression. Use an algorithm that evaluates from left to right, rather than right to left. Easiest way to do this (although somewhat inefficient) is to have a stack for the operators and single variables for the operands. One of the operand variables will hold the result of the operation (and subsequently is the first operand for each operator) while the other holds the second operand to be used in the operation.

Martha is a healer, a healthcare provider, and an experienced nurse. she wants to share her daily experiences, as well as her 12 years of work knowledge, with people who may be interested in health and healing. which mode of internet communication can martha use?

Based on your knowledge of a good network, describe what you think is a perfect network would be. what kind of information and resources could users share on this network. what would the network administrator do? what kind of communication would be used?

When making changes to optimize part of a processor, it is often the case that speeding up one type of instruction comes at the cost of slowing down something else. for example, if we put in a complicated fast floating-point unit, that takes space, and something might have to be moved farther away from the middle to accommodate it, adding an extra cycle in delay to reach that unit. the basic amdahl's law equation does not take into account this trade-off. a. if the new fast floating-point unit speeds up floating-point operations by, on average, 2ă—, and floating-point operations take 20% of the original program's execution time, what is the overall speedup (ignoring the penalty to any other instructions)? b. now assume that speeding up the floating-point unit slowed down data cache accesses, resulting in a 1.5ă— slowdown (or 2/3 speedup). data cache accesses consume 10% of the execution time. what is the overall speedup now? c. after implementing the new floating-point operations, what percentage of execution time is spent on floating-point operations? what percentage is spent on data cache accesses?