time-dependent and time-independent resources

Instructions:

It is important to understand that the project schedule is based on the cost risk as well as a part of contingency-free budgeting. Since resources are key in the cost risk analysis it is important to understand time-dependent and time-independent resources. In 250 words in APA format answers the questions. 

• What is the importance of distinguishing between time-dependent and time-independent resources?
• Does it impact the project schedules and the cost risk analysis?
• Explain and provide an example of the pros and cons as it applies to project costs.