67. List the following weak acids in order of increasing acidity (from lowest to highest.). (A) 4 ＜ 3 ＜ 2 ＜ 1 ＜ 5(B) 4 ＜ 1 ＜ 3 ＜ 2 ＜ 5(C) 5 ＜ 2 ＜ 3 ＜ 1 ＜ 4 (D) 4 ＜ 1 ＜ 2 ＜ 5 ＜ 3

38. Which of the following statements applies to the E2 mechanism? (A) It occurs with inversion of stereochemistry. (B) It occurs with racemization of stereochemistry. (C) It proceeds through the more stable carbocation intermediate. (D) The C-H and C-X bonds that break must be anti.