#"circumference of the bicycle wheel can be calculated using "##"formula "s=2 pi r#
#s=2*pi*35=219.9cm=2.199m#
#"We have to find out how many times the bicycle's wheel has"##"turned ."#
#30 km=30000meters.#
#"n:number of revolution"#
#n=30.000/(2.199)=13642.6#
#"How many seconds have passed since the wheel was turned "##"once? we must answer the question."#
#1h=3600 sec.#
#"T:Period"#
#T=3600/(13642.6)#
#T=0.26 sec#