how to calculate formula for period of a cylinder that depends on radius(cm), length(cm) and time(sec).

If a radius is 3.84 and at
length(30)=.83sec
length(100)=3.31sec
length(200cm)=6.04sec

1) to determine the relationship with radius, you have to have more than one data point.

2) I don't see a relationship with length, given the three points.