The length of river 'Narmada' is about $$1290\ km$$. Its length in meters is ________.
Correct option is A. 1290000
We know that,
$$1\ km=1000\ m$$
$$\Rightarrow1290\ km=1290 \times 1000\ m=1290000\ m$$
Hence the length of 'Narmada' river in meters is $$1290000\ m.$$