Question: Dow Jones Industrial Average The graph shows the Dow Jones Industrial Average on a particularly tumultuous day soon after the U.S. credit rating was downgraded from AAA to AA+ in August of 2011. If t represents the number of hours after 9;30 a.m., then the graph defines the Dow Jones Industrial Average D as a function of time t. If we represent this function by D = f(t), use the graph to complete the following.
(a) Find f(0) and f(6.5).
(b) Find the domain and range for D = f(t) as defined by the graph.
(c) About how many t-values satisfy f(t) = 11,000? Estimate one such t-value.
![2109_Dow.png](https://secure.tutorsglobe.com/CMSImages/2109_Dow.png)