In wireless sensor network, we usually need to combine the information gathered from multiple sensors to detect an event. To answer this question we present a new type of query, Geo-Range query. This query reports the geographic points where the average value of nearby sensors are greater than certain threshold. To perform this query, we developed two fast, efficient algorithms. The Brute-Force algorithm use exhaustive method to enumerate all possible values, which takes O(n^3) running time. The Sweep-Line algorithm applies a conceptual line sweeping through the plane. The sweep-line moves through the plane and keeps tracking all the sensor points encountered. The algorithm takes O( n^2 \log n ) running time, while it still gives exact solution to the problem. We implement and simulate our algorithms in Visual Basic.Net.