Why is is more difficult to prove a correct theory than to disprove an incorrect one?

Federalism began to spread super soon after

Which of the following is true of emotions? (a) a neurologically-intact baby can show at least six distinct emotions at birth. (b) the character of emotions changes as we develop cognitively. (c) basic emotions are culturally- and developmentally-based. (d) in general, adults cannot interpret infant emotions until the infants are 10 to 12 months old.

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: