If x2 + y2 = 106 and x - y = 4, then the value of 1x - 1y is:

Evaluate: (2.3)3 + (1.7)32.89 + 5.29 - 3.91 = ?

What is the value of (1.8)3 + (0.7)3 + 2.1 × (1.8)2 + 5.4 × (0.7)2?

What is the value of (3.8)2 - (1.2)23.8 × 3.8 + 1.2 × 1.2 + 3.8 × 2.4?