Step-by-step explanation:
6000 years = 6000 x 365 x 24 x 60 x 60
= 1.892 x 10¹¹ second
gain is 1 second
1 second is equivalent to 9.193 × 10⁹ oscillations .
In 1.892 x 10¹¹ second , change in oscillation is 9.193 × 10⁹ oscillation
in one second change in oscillation = (9.193 / 1.892 ) x 10⁹⁻¹¹
= 4.859 x 10⁻² oscillations .