In a laboratory test of tolerance for high acceleration, a pilot is swung in a circle 13.0 m in diameter. It is found that the pilot blacks out when he is spun at 30.6 rpm (rev/min). a.)At what acceleration (in SI units) does the pilot black out?

b.)Express this acceleration in terms of a multiple of .

c.)If you want to decrease the acceleration by 25.0 % without changing the diameter of the circle, by what percent must you change the time for the pilot to make one circle?
percent of time change