B. One
because an independent variable is something you change. So in a scientific experiment you only change one thing. If you happen to change more than one thing then the test becomes unfair therefore you should repeat and make sure that only one thing is changed this time.
This map shows the precipitation pattern in different parts of Florida.
Certain crops require a specific amount of annual rainfall to be successful. Which statement explains why coconut palm trees are successful in Florida?
They need an annual rainfall of 8 to 16 inches.
They need an annual rainfall of 16 to 24 inches.
They need an annual rainfall of at least 30 to 50 inches.
They need an annual rainfall of at least 120 to 140 inches.1 Attachment<span> <span>art004.gif</span></span>
