【多选题】Which screw thread has triangular thread form? (Multiple options: 10 points)
B.
55°sealing pipe thread
C.
55°non-sealing pipe thread
【单选题】A machined thread and a rolled thread, which one has better mechanical performance ?
【单选题】下列边缘型椎体结核的临床特点中,错误的是
C.
病变局限于椎体上下缘,但很快侵犯椎间盘及相邻椎体
【单选题】Based on the thread designation Rc3/4, this thread is (Single option: 10 points)
A.
Sealing internal taper pipe thread
F.
Non-sealing pipe thread
【单选题】下列边缘型椎体结核的临床特点,正确的是
C.
病变局限于椎体上下缘,但很快侵犯椎间盘及相邻椎体
【单选题】Based on the thread designation G1/2A, this thread is (Single option: 10 points)
D.
Non-sealing pipe thread
【单选题】以下关于公共艺术设计学会善变的原因描述不正确的是()
B.
现代人追求个性的表达,审美观各异,使艺术变化多元化
C.
表现形式不拘泥于传统,吸收其他各门艺术的精华
【单选题】边缘型椎体结核好发于什么部位,以成人多见