Some information is missing for #6. #7: use sine, sin35=h/5.1, h=5.1*sin35, use a calculator, h≈2.9 #23: to find the reference angle, keep subtracting the number by 360, until the remaining difference is the smallest positive number. 1406-360-360-360=326. the reference angle is 326. now look at the remainder, the terminal line of 326 degree is in the 4th quadrant between 270 and 360, the the reference angle is 360-326=34, the angle between the terminal line and the positive x axis. 34 is the answer.
