At which latitude does the Earth experience desert ecosystems due to global patterns of air ...

At which latitude does the Earth experience
  desert ecosystems due to global patterns of air
  circulation?
 
  a. 0
  b. 30
  c. 60
  d. 90
  e. more than one of these

Question 2

Which of the following represents an example
  of climate?
 
  a. July 20, 1930 was the hottest day on record
  in Washington, DC
  b. April 14th, 1921 Silver Lake, Colorado
  received 1.7 meters of snow
  c. the rainfall in Seattle, Washington on July
  4, 2010 was 2 centimeters
  d. the average summer temperature in Miami,
  Florida is 27 Celsius
  e. none of these are an example of climate