What is an example of a catalyst?

According to piaget, children have acquired the cognitive skill of conservation when they're able to a. understand that six ounces of liquid in a jar and six ounces in an elongated tube are equal. b. understand the viewpoint of other people. c. relate objects around them to their own needs. d. realize that the term heavy describes an object one way and the term big describes it another way. it is not b nor c. did this 2 x wrong..

What is the term for a water wave that is created by an underwater earthquake?

How does climate change affect producers?