Answer: 2018; $21,500
Explanation:
The 't' in D(t) represents how many years after 1995 the function is referring to. This question has the 't' at 23 so this is 23 years after 1995.
= 1995 + 23
= 2018
The average household debt is given in thousands of dollars therefore;
= 21.5 * 1,000
= $21,500
In the year 2018, the total average credit card debt for a U.S. household will be $21,500.