Chapter 3 problem 10 solution diagram 1 on page 248, black move 2 seems an error. if black plays atari to capture 3 stones, white has no answer that kills.
Chapter 3 problem 24 solution diagram 1 on page 280, black requires a ko threat, but has none. The next diagram shows black capturing white group, but no ko threat and response is illustrated and white would have another stone on the board.