Problem 1213. What gear ratio does the cyclist need?

A cyclist (perhaps including our famed Codysolver the cyclist http://www.mathworks.com/matlabcentral/cody/players/1841757-the-cyclist) operates a bicycle most efficiently when turning the pedals at a specific rotational rate. it turns out that almost all real engines are most efficient in a limited range of rotation rates. You'll be given a minimum and a maximum cyclist pedaling rate in revolutions per minute (rpm). You get a wheel diameter in inches and the height of the compressed tire above the wheel in inches. You will be given a speed that the bicyclist wants to travel in miles per hour (mph). You need to compute the gear ratios required to allow the cyclist to travel at the pedaling rates from the input and provide it as a two element row vector.