Ответ:

  1. \(5{,}9 \times 72 = 5{,}9 \times (70+2)=413+11{,}8=424{,}8\).
  2. \(6{,}8 \times 5{,}7 = 38{,}76\).
  3. \(0{,}56 \times 8{,}3 = 4{,}648\).
  4. \(0{,}73 \times 0{,}59 = 0{,}4307\).

Ответ: 424,8; 38,76; 4,648; 0,4307.