(i) 28.7 pm:
1 pm = 10-12 m
∴ 28.7 pm = 28.7 × 10-12 m
= 2.87 × 10-11 m
(ii) 15.15 pm:
1 pm = 10-12 m
∴ 15.15 pm = 15.15 × 10-12 m
= 1.515 × 10-11 m
(iii) 25365 mg:
1 mg = 10-3 g
25365 mg = 2.5365 × 104 × 10-3 g
Since,
1 g = 10-3 kg
2.5365 × 101 g = 2.5365 × 101 × 10-3 kg
∴ 25365 mg = 2.5365 × 10-2 kg