A city will be affected. Drawing proves that drawing a circle with A as the center and 200 kilometers as the radius will affect a city. Or the vertical line passing through point A is BF, and the length is 150 km, less than 200 km, so the typhoon center will affect city A.
(2) If City A is affected by a typhoon, how long will it last?
Use Pythagorean Theorem to calculate chord length first, and then calculate time.
√(200^2- 150^2)=50√7
2*50√7/ 10√7= 10 hour
A city was affected by typhoon 10 hour.