Stars and the Universe — practice question

The Milky Way’s diameter is about 100 000 light years. Express this distance in metres.

• A$9.5 \times 10^9\,\text{m}$
• B$9.5 \times 10^{15}\,\text{m}$
• C$9.5 \times 10^{17}\,\text{m}$
• D$9.5 \times 10^{20}\,\text{m}$