The answer to your question is C)26
There are 100 centimeters in a meter
100 divided by 5 is 10
You need 10 5 centimeter squares to completely cover 1 meter square without overlapping
If you are rolling a single six sided die numbered 1-6, you find that only 1,2,4, and 5 are factors of 20. Now the theoretical probability of an event is the ratio comparing the number of desired outcomes to the total outcomes possible.
In this case: we have 4 desired outcomes out of a total 6 outcomes possible with a single roll the die.. therefore, the probability you seek is

or approximately 67%.
V = Displacement / Time
V = 5 m / 15 s
V = 1/3 m/s or 0.33 m/s