Seismic ground noise describes the persistent vibration of the ground due to surface waves generated from traffic, heavy machinery, winds, ocean waves, and earthquakes. A group of civil engineers investigated the structural damage to a three-story building caused by seismic ground noise in Earthquake Engineering and Engineering Vibration (March, 2013). The methodology involved modeling the acceleration Y (in meters per second-squared) of the seismic ground noise using a normal probability distribution. Consider a normal distribution for Y with μ = .5 m/s² and σ = 0.1 m/s². Find a value of acceleration, Y = a, such that P(Y > a) = .70.