It seems almost unbelievable that so many students are sick during midterms and final exams, but actually these are times of stress that the effectiveness of the immune system to fight off illness. Group of answer choices

From the examples below, choose the best examples of industries in african countries and their influence on economic development. select all that accurately represent african economies and factors of production. because agriculture remains central to the success of the mali's economy, any change to climate (such as drought) or price of crops significantly affect the country as whole. the thriving manufacturing industry in chad's northern region sustains the country's economy as a whole. egypt's manufacturing and export of cotton is the primary focus of the economy in the country. morocco serves as a representative of service industries in africa with a growing tourism market.

Recently, there has been pressure to loosen clean air standards. use economic arguments to support or oppose this proposed action.

Donald is studying the eating habits of all students attending his school. he samples the population by dividing the students into groups by grade level and randomly selecting a proportionate number of students from each group. he then collects data from the sample. which type of sampling is used? select the correct answer below: systematic sampling convenience sampling stratified sampling cluster sampling