A satellite uses a circular antenna array that rotates to maintain a constant data transmission rate to a ground station. The antenna array has a maximum radius of 2.0 meters. For optimal data transmission, the edge of the array must move at a constant linear speed of 5.0 m/s. The rotation speed can be adjusted as the active transmission elements move from an initial radius of 0.55 meters to the full extent of the array. Determine the rotational frequencies (in units of rpm) when the active elements are at the initial and maximum radii.