б) 10¹² + 3 × 10⁸ + 9 × 10⁵ + 10 = 1000000000000 + 3 × 100000000 + 9 × 100000 + 10 = 1000000000000 + 300000000 + 900000 + 10 = 1000300900010
Ответ: 1000300900010