Some environmental changes that occur on Earth accumulate very ...

[kamilo84]

Some environmental changes that occur on Earth accumulate very slowly so that careful scientific study over the long term is required to understand what is occurring.
  Indicate whether the statement is true or false

Question 2

The two most common elements found in Earth's crust are ____.
 a. silicon and magnesium
  b. sodium and carbon
 c. iron and aluminum
 d. silicon and oxygen
 e. carbon and potassium

[jomama]

Answer to Question 1

T

Answer to Question 2

d