A small city is divided into four quadrants of 25 square kilometers each and has two fire trucks that can only be dispatched to one quadrant in a given day. The number of fires in the city on a given day follows a Poisson measure N with a characteristic measure. 

   

What is the probability that there are fires in at least three quadrants on a given day? 

   

What is the expected number of fires in the city on a given day? 

H(A) = 10 da x dy for AC-5,5] x [-5, 5] (say).