New PMP Question & Answers with explanation

Funding requirements for a project are usually in incremental amounts that are not continuous. These increments appear as a step function in the graph depicting Cash flow, Cost baseline and Funding. Any gap at the end of the project between the funds allocated and the cost baseline represents:
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Lucy is currently preparing a high-level cost estimate for her project in the initiation phase. With the limited detail available to her, what would you expect the range of her estimate to be, and what would you call such an estimate?
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An estimating technique that uses a statistical relationship between historical data and other variables (such as square footage in construction or lines of code in software development) is known as:
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Your project is midway through a delivery schedule. As the project manager, you want to determine how much work remains. Which is the most accurate way to determine the remaining work the project team must carry out?
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A project is estimated to cost $50,000 with a timeline of 50 days. After 25 days, the project manager finds that 50 percent of the project is complete and actual costs are $50,000. What is the Cost Performance Index (CPI)?
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