Two different formulations of primer paint can be used on aluminum panels. The drying time of these two formulations is an important consideration in the manufacturing process. Twenty panels are selected; half of each panel is painted with primer 1, and the other half is painted with primer 2. The drying times are observed and reported in the following table. Is there evidence that the median drying times of the two formulations are different? Use the sign test with a =0.01.