An agricultural field trial compares the yield of two varieties of tomatoes for commercial use. The researchers divide in half each of 10 small plots of land in different locations and plant each tomato variety on one half of each plot. After harvest, they compare the yields in pounds per plant at each location. The 10 differences (Variety A - Variety B) give the following statistics: x = 0.46 and s = 0.92. Is there convincing evidence that Variety A has the higher mean yield? Carry out a complete significance test.