(2) On February 1, Arshak's investment account has a balance of $19,800. He deposited $1,200 on April 1 and $2,600 on May 1. He withdrew $8,400 on July 1. On November 1, Arshak's balance was $14,820. Find Arshak's approximate dollar-weighted annual yield for this nine-month period using (2.6.5)