Definition: In this task, you are given a context tweet, a question and corresponding answer of given question. Your task is to classify given passage into two categories: (1) "yes" if the given context is useful in answering the question, and (2) "no" if the given context is not useful.
Input: Context: At 1:21 before launch, a thrust vector control actuator for the Falcon 9's 2nd stage failed to perform as expected. @SpaceX is evaluating.— NASA (@NASA) January 6, 2015 Question: what happened to the thrust vector control Answer: it failed

yes