Help this is missing and I need help

U.s. history 1.documentary analysis what steps did taylor’s family take to prepare her freedom

What was the name of the theory that said that if one country in a region fell to communism, others would surely follow? 1) domino theory 2) arms race 3) brinkmanship 4) containment theory

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