What is Google's Rich Answer Box?
Google's rich answer box is a new feature that delivers direct responses to user queries at the top of the search page, presenting immediate answers to their questions. As people enter queries into the search bar, Google analyzes its results to deliver the closest potential answer.
Google rich answer box is a snippet tool to answer the question right away, and the users don't have to wait or click any site to get the answer. It give the desired answer at the top of the page.