In the Telecommunications Act Congress “imposed specific limitations on the traditional authority of state and local governments to regulate the location, construction, and modification of facilities,” for wireless telecommunications. The Act empowers D to “prescribe such rules and regulations as may be necessary in the public interest to carry out [its] provisions.” The Act requires state or local governments to act on wireless siting applications “within a reasonable period of time after the request is duly filed” and allows applicants to sue in any court of competent jurisdiction. In reality, local jurisdictions imposed very long delays. D determined 90 days to be the presumption of reasonableness for a new antenna on an existing tower and 150 days for a new tower. Ps opposed the rule. The court of appeals held Chevron applied to whether D possessed statutory authority to adopt the 90- and 150-day timeframes. It held that D’s interpretation of its statutory authority” was a permissible construction of the statute. Ps appealed.