Which of these steps would most likely be part of a lab procedure? a. Write a hypothesis to answer a question

b. Write a title at the top of a completed lab report

c. Record the time to complete a chemical reaction.

d. Create a question on the cause of a chemical reaction

at the bottom

explanation:

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.