Check the picture below.
notice chord QR is a diameter, thus the vertex at P has a right-angle by Thales theorem.
Your question is incomplete .....
Answer: 7n−13
Step-by-step explanation:
First, familiarize yourself with the math formula, use memorization techniques (ex.flashcards), understand the formulas, and get plenty of sleep.
If it flaps its wings 159 times in <em>3 </em>seconds, it'll be able to flap them <em>1/3 </em>of that amount in 1 second, which would be 1/3 · 159 = 53 flaps per second.