Answer:
We conclude that at restaurants in 2016 will be spent 752.16$.
Explanation:
We know that since 2006, the amount of money spent at restaurants in a certain country has increased at a rate of 6% each year. In 2006, about $420 billion was spent at restaurants.
We calculate how much will be spent at restaurants in 2016.
We use the formula:

where are:

we get

We conclude that at restaurants in 2016 will be spent 752.16$.