A mountaineer carries a backpack of mass 10kg. At sea level where g=9.80m/s2, the pack’s weight is W1. On a high peak where g=9.70m/s2, its weight is W2. By approximately what percentage does the weight decrease when the mountaineer reaches the peak?
(a) 0.51%
(b) 1.02%
(c) 1.53%
(d) 10.2%