According to Lorenz, ducklings form strong attachments during a critical period. These bonds are difficult to break because they are based on familiarity, even though the attachments may not be to the parent. He called this process bonding
distancing
imprinting
linking
mimicking

The difference of sample means of two populations is 55.4, and the standard deviation of the difference of sample means is 28.1. which statement is true if we are testing the null hypothesis at the 95% confidence level? a. the difference of the two means is significant, so the null hypothesis must be rejected. b. the difference of the two means is significant, so the null hypothesis must be accepted. c. the difference of the two means is not significant, so the null hypothesis must be rejected. d. the difference of the two means is not significant, so the null hypothesis must be accepted.