Disorder in the universe increases because
a. spontaneous changes produce more order in a system.
b. work produces disorder in a system.
c. work produces waste heat, which leaves a system.
d. all of the above

Select each correct answer. more than one answer may be correct. which of the following is a characteristic of unicellular organisms? they can possess tissues and organs. all of their functions are performed by a single cell. they are usually microscopic. each of their cells is specialized to perform a specific function.

Can someone me with questions 15 to 17 plz.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation: