I NEED HELP PLEASE!! What can the author accomplish by using a tone?

Read the excerpt from the common sense of bicycling: bicycling for ladies. one incorrect move or poise of any part of the body will be noticed as eccentricity. an erect position, steady on the saddle, but when all is done, the crowning grace is that of apparent ease. they who pitch the body forward with every downward push, make the bicycle appear to be a tread mill, requiring so many horse power to move it. rocking from side to side creates a chafing sensation—to those looking on. saddles too low, toes in, knees out, elbows high, head low, back humped, hurts the sale of bicycles. to be correctly positioned on a bicycle seat, which steps should the rider avoid? check all that apply.