B
digestive system absorbs water and nutrients and circulatory systems carries nutrients to cells and excretory system helps eliminate waste
C. a hydrogen bond is the answer just took the test good luck on the res
Answer:
D) friction between wind and surface water
Explanation:
I believe
Niacin is also known as Vitamin B3. It is needed by the body because it produces the coenzymes NAD and NADP which are responsible for the body's metabolic reactions. If you are deficient of niacin, the body can synthesize it using tryptophan. Food sources of tryptophan include eggs, liver, peanut butter and dairy products.
