The odour from a gas A takes six seconds to reach a wall from a given point. If the molecular weight of gas A is 46 gram per mole and the molecular weight of gas B is 64 grams per mole. How long will it take for the odour from gas B to reach the same wall from the same point approximately
| A. |
6 sec |
| B. |
7 sec |
 |
| C. |
8 sec |
| D. |
9 sec |