43.278 kg - 28.1 g use significant figures rule

You cannot directly subtract the given values because their units are different. To be consistent, let's convert kilograms to grams with the conversion that 1,000 g = 1 kg.

43.278 kg(1,000 g/1 kg) - 28.1 g = 43249.9 grams

In subtraction, you will base the number of significant figures to the least of the given data. Since 28.1 has 3 significant figures, the answer should also contain 3 significant figures. Thus, it is much more convenient to report it in terms of kilograms.

43249.9 grams * 1 kg/ 1,000 g = 43.2 kg

Answerthe energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.explanationwe define electric potential as the ratio electric potential energy to the charge,    then the following gives us the potential difference,      the formula  may be on your formula sheet.the change in electric potential energy would be the energy that would needed to move it from point a to point b. solving for that, we get    using q = 8.00  × 10⁻¹⁹ c and  δv = 2.00 v, we get    the energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.

The answer is b. all other properties are crucial.