Answer:
Explanation:
F = GMm/d²
F = 6.67259 x 10⁻¹¹(2.39)(0.016) / 0.0681²
F = 5.5019685...x 10⁻¹⁰ N
round as appropriate, probably no more than 3 significant figures.
Value of G seems low, but well within the 3 significant figures of the other numerals. I typically see G = 6.674 x 10⁻¹¹