Answer:
1. using hand sanitizer with at least 60% alcohol
2. the probability of contracting a disease is lower if you wash your hands than if you don't wash your hands. That is: P (disease if you wash your hands) < P (disease if you don't wash your hands).
Explanation:
1. Noteworthy is the fact that alcohol based hand sanitizers provide good protections to germs, viruses as when one washes his hands with soap for 20 seconds. This was indicated in the video as an acceptable alternative to washing your hands for 20 seconds with respect to preventing illness.
2. Remember, probability implies an assumption of possiblity or likelihood of something happening. Thus, the video's message implies that when people wash their hands it reduces the likelihood (that is, the probability) of contracting diseases. One stands a lower chance of : P (disease if you wash your hands) < P (disease if you don't wash your hands).