For boys in the United States, the first signs of puberty usually occur around age

Approximately what proportion of American adolescents who are clinically depressed have at least one other psychological disorder?

A) 4/5 B) 2/3 C) 1/2 D) 1/4

Which of these is NOT one of the levels of discourse representation?

a) situation model b) surface code c) text base d) analog code