Answer:
17 h
Step-by-step explanation:
The command sent to the Voyager I is a radio wave signal, which travels at the speed of light:
![c=3.0\cdot 10^8 m/s](https://img.qammunity.org/2020/formulas/physics/middle-school/556h2flqn41ltgwpw2zl07hf33kpkh2pd9.png)
The distance between the Voyager I and the Earth is
![d=1.8\cdot 10^(13) m](https://img.qammunity.org/2020/formulas/physics/high-school/w794xwlmjvpvdgeq2v29430nhut8ins85i.png)
So, the time taken for the signal to reach the probe is
![t=(d)/(c)=(1.8\cdot 10^(13) m)/(3\cdot 10^8 m/s)=60,000 s](https://img.qammunity.org/2020/formulas/physics/high-school/a1c0gu0eagihkhoducozmd2gsywwy82otd.png)
Consindering that the number of seconds in 1 hour is
![60\cdot 60 = 3600 s](https://img.qammunity.org/2020/formulas/physics/high-school/xkqzdvzec75ekp8ubc1mgjegn1ryrmnj70.png)
Then the time elapsed converted into seconds is
![t=(60000 s)/(3600 s)=16.7 h \sim 17 h](https://img.qammunity.org/2020/formulas/physics/high-school/iq87yz70r2ki3tj41tjcrlu13jf6ey50go.png)