The periodic table was createdby grouping elements according to their properties. Oxygen is a gas that has 6 valence electrons and is colorless. Which of the following unknown element would be grouped along with it? A. Boron B. Selenium C. Aliminum D. Phosphorou

2. which of the following statements does not accurately describe stem cells? a. embryonic stem cells make up the inner cell mass of a blastocyst. b. with more research, stem cells may be used to repair or replace damaged cells. c. the use of stem cells is without any objections since it can be used in therapies to humans. d. adult stem cells are multipotent and can differentiate into many types of cells.