The Answer Is B.
To Find The Mean, You Add Up Every Number And Divide By How Many Numbers There Were.
136 + 145 + 123 + 140 + 126 = 670
670 Divided By 5 = 134
The Mean For The 4 Weeks Was 136.
The Mean For The 5 Weeks Was 134.
The Mean Decreased By 2. Your Answer Is B.