What was the concern some northerners had regarding the freed slaves?

There are traits like blood type and eye color, and others like speaking english or having a scar. what are the terms used to describe these different types of traits? how are each defined?

In the 1950s and 1960s, chief justice earl warren was a strong advocate for?

Often, a goby fish and a shrimp will live together in a burrow the shrimp has dug in the sand. the shrimp is almost blind and therefore is unable to see predators approaching when he is outside of the burrow. when the shrimp is in danger, the goby fish touches the shrimp with its tail to warn him. then, both go back into their burrow for safety. which type of relationship does this represent? a. mutualism b. parasitism c. commensalism d. predator/prey