Answer the question in a note or paper

Use sign test to see whether there is a difference between the number of days required to collect an account receivable before (B) and after (A) a new collection policy. Test at 5% level. B 33 36 141 32 39 147 34 29 32 34 40 42 33 A 35 29 38 134 37 47 36 32 30 34 41 38 37 Use normal (Z) property for using tabulated value. Also compare sign test with run-test