PLEASE HELP! How do these samples react with sulfuric acid

B"hf and f-"  is the correct answer took the test on edgenuity and got it right     

Ansaquatic plants;  

Chromosomes can be used more than once atoms are all different

Most elements have more than one naturally occurring isotope. as you learned previously, the atoms of those isotopes have the same atomic number (number of protons), making them belong to the same element, but they have different mass numbers (total number of protons and neutrons) giving them different atomic masses. so which mass is put on the periodic table for each element? is it the most common isotope’s mass? the heaviest mass? this activity will answer that question.