Aspects described herein relate to a network for providing air-to-ground wireless communication in various cells. The transmittance of light having a wavelength of 550 nm measured at a thickness of 2 mm is equal to or greater than 40%. The effective unshared electron pair content nM of this compound satisfies \u201c3. The pusher and crash stop portions eliminate the need for a separate crash stop in the disk drive. The electrochemical meter obtains viscosity of the liquid sample according to a time difference between the first and second pulse signals.