Acertain human red blood cell has a diameter of 0.000007 meters. write an expression that represents this diameter, in meters in scientific notation. equation

By definition we have to:
 Scientific notation, also called pattern or notation in exponential form, is a way of writing numbers that accommodate values too large or too small to be written in a conventional manner.
 The use of this notation is based on powers of base 10.
  A number written in scientific notation follows the following pattern:
 
 The number m is called "mantissa" and e the "order of magnitude"
 For this case we have:
 0.000007
 Using the definition, we have that the measure of the diameter in scientific notation is:
 
 
 An expression that represents this diameter, in meters in scientific notation is: