Ricardo wants to study the academic performance of graduate students in the u. s. first, he decides that he will study schools in only 15 states and randomly selects those states. he then randomly selects 30 schools from these 15 states. over a period of 3 months, ricardo travels to these 30 schools and studies the academic performance of their students. identify the sampling technique used by ricardo in this scenario

An important source of public scrutiny is "watchdogs." these are: the efforts of a firm's competitors, including how often the competitors attack the firm's strategies. taxpayer-supported government agencies that limit a firm's ability to compete in foreign markets. companies designated by the government to only produce products that support the government defense program. socially conscious groups that make it their mission to measure the social responsibility levels of businesses, and provide consumers with their opinions about the level of corporate responsibility of various companies.