On Monday, Johnny's mother gave him cookies and milk after he had played quietly for 10 minutes. On Tuesday, she required 20 minutes of quiet play before treat time. On Wednesday, she gave him cookies only after he played quietly for a full half hour. Johnny was taught to play quietly for extended periods through . Group of answer choices shaping secondary reinforcement spontaneous recovery fixed-ratio scheduling

In 1990, the average income for an american worker was $1,518 per month. in 2000, the average income for an american worker was $2,632 per month. during this time period, a basket of necessities (food, housing, etc.) increased from $657 per month in 1990 to $1,402 per month in 2000. the real value of income ▼ increased decreased over that 10-year period.

The process of rocks breaking down and becoming other rocks

Cooperation among oligopolies runs counter to the public interest because it leads to underproduction and high prices. in an effort to bring resource allocation closer to the social optimum, public officials attempt to force oligopolies to compete instead of cooperating. consider the following scenario: suppose that the presidents of two auto manufacturing companies exchange text messages in which they discuss jointly raising prices on their new lines of hybrid suvs. this illegal communication would violate which of the following laws? the sherman antitrust act of 1890 the robinson–patman act of 1936 the celler–kefauver act of 1950 the clayton act of 1914