As San Francisco and other cities in the Bay Area commemorate the anniversary of the 1989 Loma Prieta earthquake, we are reminded once again of the need to get prepared for the next natural disaster. The 6.9 magnitude earthquake not only resulted in collapsed homes, displacement of residents, but it also was a terrifying reminder of the need to reinforce the structures we use every single day.
The distance between scale markings on the horizontal scale is 100 km. Comparison of the vertical and horizontal scales indicates that the horizontal scale distance between tic marks is __<u>100</u>_ times that of the vertical scale.
