please helo with 1&2

There are three stocks in a price-weighted index: ABC$1002760 What is the average value for the index? (Keep 2 decimal places) Assume the following five companies are used in computing an index: If the index is price weighted, what will be the value of the index on December 31,2007 ? (Take the average price on December 31,2007 , and divide by the average price on January 1, 1984, and multiply by 100 .)