28. When did the writer write this message? (A) October 15th (B) November 20th (C) After November 20th (D) Between October 15th and November 20th

35. What are the advantages of tipis mentioned in this passage? (A) Tipis are quite light and cheap. (B) The tipi has a living capacity of more than 10 people. (C) A good tipi can protect people from heavy rains and strong winds. (D) People can use the same tipi for hundreds of years.