The Mercer Island Station of Sound Transit Light Rail is located in the center of I-90 near the Mercer Island Town Center and the Mercer Island Park and Ride. Riders can enter at either 1) 77th Avenue Southeast at the West Entrance, or 2) 80th Avenue Southeast at East Entrance. Walkers or Bicyclists can access the station from the nearby Mountains to Sound Greenway Trail.
East Link is a voter-approved project to expand light rail from downtown Seattle to the Eastside with stations serving Mercer Island, south Bellevue, downtown Bellevue, Bel-Red, and Redmond's Overlake area. The expected opening date has been adjusted repeatedly. Line 2 will connect to light rail Line 1 already operating between Seattle and Sea-Tac Airport.
To solve this multi, first, look for the 4-digits address number at the virtual Posted Coordinates at the West Entrance. Second, look for the 4-digits address number at the virtual WP coordinates at the East Entrance. Next identify the 2-digits that are common to both the West and East Entrances' address numbers. That 2-digit number is the "Key Word" for Certitude to reveal the Final Coordinates and a hint.
You can validate your puzzle solution with
certitude.