Macbeth's ambition is driven by a number of factors. For one, he has a deep internal desire for power and advancement. However, that is not exactly why he turns to crime. It takes two outside forces to ignite this hunger and push him to take violent action to obtain power.
I might be wrong but diversity and safety are two things i can think of. If what we're seeing is a fire exit then it displays the safety issues found in early workplaces. and there is also a lack of diversity between the workers on the stairs.
B. If you look at the dates, the earliest instance of the plague started in the south. Then, it continues to spread upwards and to the west, and the dates continue chronologically, from 1347 to 1349.
