Becky's speed is her distance travelled which is 30 km divided by her time travelled of 2.5 hours which gives her average speed of 12 km/hour which is a quite good speed if she was say riding a bicycle and which would give her a good aerobic workout.
Spillages on a tiled floor, a highly polished floor surface, a damp smooth surface with no mat.
Answer:

Explanation:
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In this case, since know the volume, temperature and pressure of the initial containers, we can compute the moles of each gas prior to the opening of the valve as shown below:

Next, we add them up to obtain the total moles:

Now, the total volume:

Finally, the total pressure is computed by using the ideal gas equation:

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