The following code will dim an LED. How many times will the body of this loop run? 22 brightness_step = 1/20; 23- Efor i=20:-1:1 24 write PWMDutyCycle (a, '19', i *brightness_step); 25- disp (i); 26- pause (.5); 27- end 20 times 1 time 1/20 times O 10 times