Reasonable suspicion does not apply if a person simply refuses to answer questions or is of a certain ethnicity or race. If a person is suspected of committing a violent crime, such as robbery or murder, the police officer may frisk the suspect's clothing to check for weapons.
Middle age technically refers to reaching an age where you have lived half the average life expectancy for your gender. The average midpoint of life is now about 40 for women and 38 for men (men tend to die 6 to 8 years before women). In comparison, 100 years ago women arrived at middle age by 22, mainly because so many died in childbirth.
Midlife crisis is a term first coined by Elliott Jaques referring to a critical phase in human development during the forties to early sixties, based on the character of change points, or periods of transition. The period is said to vary among individuals and between men and women.