Why is the following situation impossible? Emily challenges David to catch a $1 bill as follows. She holds the bill vertically as shown in Figure P2.47, with the center of the bill between but not touching David’s index finger and thumb. Without warning, Emily releases the bill. David catches the bill without moving his hand downward. David’s reaction time is equal to the average human reaction time. where vi = m/s , a = m/s^2 and t = s ?