А) 2 * (4 + 5) = 2 * 9 = 18
б) 2 * 4 + 2 * 6 = 2 * 10
2 * 3 + 2 * 6 = 2 * 9
2 * 2 + 2 * 5 = 2 * 7
2 * 7 + 2 * 1 = 2 * 8
в) 2 * 35 = 2 * 30 + 2 * 5 = 60 + 10 = 70
2 * 19 = 2 * 10 + 2 * 9 = 20 + 18 = 38
2 * 26 = 2 * 20 + 2 * 6 = 40 + 12 = 52
2 * 39 = 2 * 30 + 2 * 9 = 60 + 18 = 78
2 * 47 = 2 * 40 + 2 * 7 = 80 + 14 = 94