What element is most important for adding strength to hair, feathers , and outer skin? a. oxygen b. hydrogen c. sulfur d. phosphorus

An example of a trait that would be considered acquired and inherited is a. a cleft chin b. muscle tone c. scar tissue d. freckled skin

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen

You are working in the lab and are working with the same element but with varying isotopes of the element. you are working with c-11, c-13, c-14, and c-15. what is the average atomic mass of this element? (use periodic table) a- 12 b-15 c-14 d-13