Analyze the effect that plentiful harvests had on population in the ancient civilizations of the mainlands river valleys

Dr. robbins wants to know if there are different opinions regarding the value of public school education between native americans who have at least one relative who attended indian boarding school and native americans who have no family experience with indian boarding school. dr. robbins contacts 35 native american participants in each group. he wants each group to include younger as well as older adults, and a mix of male and female participants. he asks each person to complete a survey about their attitudes toward public education. the design of this study is:

This cartoon appeared in 1916. the topic of the cartoon isa)the reason for the start of world war i.b)the success of us submarines in world war i.c)the military alliance between germany and mexico.d)the attitude in the us towards submarine warfare in world 

Surfaces of paintings—such as paper, canvas, and pottery—are referred to technically as