If a company or individual posting to craigslist is having trouble with competitors, fake posts, harassment, etc., there are a number of ways to get things done. I'm sure that Craigslist, like every other site, makes people jump over a few hurdles before they can get in touch with a live human.
Calories Burned. On average, a 150-pound person burns 91 calories biking for 20 minutes at a leisurely pace of less than 10 miles per hour, according to the Calorie Control Council's Get Moving Calculator. The caloric burn increases to 136 calories when intensity escalates to a moderate pace, 12 to 13.9 miles per hour.
The amount of calories you burn biking in 20 minutes depends on how much you weigh and how fast you cycle. A leisurely bike ride of 10 mph or less will burn fewer calories than cycling faster in a 20-minute period. A 150-lb. person biking at less than 10 mph will burn 90 calories in 20 minutes, according to the Calories Burned Biking website.