An Arrow Strikes a Circular Target at Random at a Point

Short Answer

An arrow strikes a circular target at random at a point (x, y), using a coordinate system with origin at the center of the target.The probability density function for the point where the arrow strikes is given by $p ( x , y ) = \frac { 1 } { \pi } e ^ { - x ^ { 2 } - y ^ { 2 } }$ What is the probability that the arrow strikes within 0.45 feet of the center of the target.