Physical abilities (such as muscular strength, reaction time, sensory keenness, cardiac output) reach their peak: a) shortly after the onset of pubertb) when people reach their mid-20sc) uring middle adulthoodd) d shortly after the birth of your first child.

the money supply is the total amount of money available in the economy. how do changes in the money supply affect people and businesses?

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.