How many neutrons does x have if it’s atomic number is 28 and it’s mass number is 71

Which of these best describes an ionic bond?

Which class of molecules functions as chemical signals? hormones water carbohydrates proteins

Astudent is trying to create a table that compares hypotheses, theories, and laws. hypothesis theory law do scientific researchers formulate it? yes yes yes does it explain why things happen? yes yes no yes yes yes is it used to make predictions? no yes yes which of the following questions would most likely fill the blank in the table? is it an intelligent guess? is it newly formulated? is it based on observations? has it been proved?