Respuesta :

Answer:

  • 3 significant figures

Step-by-step explanation:

Problems given:

  • - 2000 + 20.5 = - 1979.5 ≈ -1980.0 ⇒ 3 significant figures
  • - 106.2 + 54.07 = - 52.13 ≈ -52.1 ⇒ 3 significant figures

Zeros at the end are not counted as significant figures