1- The normal annual precipitation of five rain gauges P, Q, R, S, and T are respectively 125, 102, 76, 113 and 137 cm. During a particular storm the precipitations

recorded by stations P, Q, R and S are 13.2, 9.2, 6.8, and 10.2 cm,respectively. The instrument at station T was inoperative during that storm.Estimate the rainfall at station T during that storm.