Final answer:
Absence due to lateness is determined by individual school policies. Probabilities involving time intervals can be calculated using the lengths of the specified intervals compared to total possible intervals, such as the probability of waiting less than 12.5 minutes for a bus in a 15-minute period being 5/6.
Step-by-step explanation:
The question seems to be about understanding school attendance policies and probabilities related to different scenarios. However, it is not clear-cut which specific situation you're asking about regarding lateness and being marked absent, as this can vary by school or district policy. Without a universal rule, we cannot say for sure if it's 5, 10, 15, or 20 minutes late that will result in being marked absent. Policies on this may be detailed in a student handbook or by inquiring directly with the school administration.
As for the probability questions, those are better answered using information about uniform distributions and conditional probabilities. For example, if waiting time for a bus is uniformly distributed between zero and 15 minutes, the probability of waiting less than 12.5 minutes is calculated by finding the length of the interval from zero to 12.5 minutes, which is 12.5 minutes, and dividing it by the total interval length, which is 15 minutes, resulting in 5/6 or about 0.8333.