下图表示一个某病家族的遗传系谱，据图回答（有关基因用A、a表示）：
Ⅳ10为杂合子的概率为（）
参考答案：2/3
Which book would you recommend to someone interesten in children’s mental imanges?（）
A.Connecting Animals and Children in Early Childhood.
B.Songs in Their Heads:Music and Its Meaning in children’sLives.
C.Big Ideas for Little Kids: Teaching Philosophy Through children’s Literature.
D.Young Children as Artists:Art and Design in the Early Years and Key Stage 1.
故障率曲线无明显磨损故障期的设备，故障率随时间延长而缓慢增加，可采用（）维修方式进行维修。
A．定时
B．定期
C．视情
D．事后
