a light flashes every 20 seconds, how many times will it flash in ? of an hour?	Pick one:
A) 550 B) 600 C) 650 D) 180 E) 750
1flash=20sec   for 1 min=3flashes   so for 1 hour=3*60= 
<gadget id="calculator">3*60</gadget>
<output>180</output>
180 flashes.   ANSWER:180
<result>D</result>
a light flashes every 20 seconds, how many times will it flash in ? of an hour?