Logarithmic equations and inequalities

1003159004

Level: 
B
Which of the given numbers is the sum of all the solutions of the equations \( \text{(1)} \) and \( \text{(2)} \)? \[ \begin{aligned} 10^{x-1}&=2 &\text{(1)} \\ 2^{1-x}&=5^x &\text{(2)} \end{aligned} \]
\( \log⁡40 \)
\( \log⁡22 \)
\( \log12+\log_7⁡2 \)
\( \log12-\log_7⁡2 \)