Respuesta :

Answer: C

Step-by-step explanation:

S = [tex]\frac{a}{1-r}[/tex]

a = 80, r = [tex]-\frac{1}{4}[/tex]

S = [tex]\frac{80}{1-(-\frac{1}{4})}[/tex]

  = [tex]\frac{80}{\frac{5}{4}}[/tex]

  = [tex]\frac{80*4}{5}[/tex]

  = 64