As part of a project for her economics class, Joan constructed her own stock index to analyze. The stock index is made up of three stocks as shown in the table below.

Analyze the stock index along with Joan by answering the questions below. 

Part I: What was the value of Joan's index on day 1?

Part II: What was the value of Joan's index on day 8?

Part III: By how many points was Joan's index up or down from day 1 to day 8?

Part IV: What was the rate of change of Joan's index from day 1 to day 8? Give your answer to the nearest hundredth of a percent.

Part V: If the rate of change of Joan's index from day 8 to day 15 is the same as the rate of change of the index from day 1 to day 8, what will be the approximate value of the index on day 15 to the nearest hundredth? Use your answer from part IV in your calculation.