What transports food materials to the body cells and waste materials to organs for elimination?

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..

Types of scientific inquiry that biologist engage in that cannot be completely controlled

Up to what percentage of the world's flora consisted of cycads during the triassic period? 100% 75% 50% 20%