Which one of the following statements is correct?
cells form tissue, and systems form organs
cells form systems, and systems form organs
tissues form organs, and organs form systems
cells form organs, and organs form tissues

Stoichiometry- i need with 14 and 15! an explanation would be appreciated!

Examine the false statement. compounds are the smallest unit of an element that occur most commonly in nature. select the rewording of the statement that is true. a: atoms are the smallest unit of an element that commonly occur in nature. b: molecules are the smallest unit of an element or compound that commonly occur in nature. c: molecules are the smallest unit of a compound that occur on the periodic table. d: compounds are the smallest unit of an element that occur on the periodic table

An object of mass 10.0 kg and volume 1000 ml and density 10 g/ml sinks in water who’s density is 1.0 g/ml. what is the mass of the water which has been displaced in kilograms