Respuesta :
Answer:
[tex] \frac{10\% +20\% + 70\% }{250 \: million} \\ \\ \\ \frac{ \frac{10}{100} + \frac{20}{100} + \frac{70}{100} }{250 \times 10 ^{6} } = \frac{ \frac{100}{100} }{250 \times {10}^{6} } \\ \\ \frac{1}{250 \times {10}^{6} } = 4 \times {10}^{ - 9} [/tex]
I hope I helped you^_^