Anewly discovered solar system is found 600 billion kilometers from the sun. how many au does this represent?

Write a recursive sequence that represents the sequence defined by the following explicit formula:

Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?

The sum of two numbers is 86, and their difference is 20. find the two numbers