單項(xiàng)選擇題
A.≥250N/50mm B.≥300N/50mm C.≥350N/50mm D.≥450N/50mm
A.≥450N/50mm B.≥350N/50mm C.≥300N/50mm D.≥250N/50mm
A.90℃ B.95℃ C.100℃ D.105℃
A.≥250N/50mm B.≥300N/50mm C.≥350N/50mm D.≥500N/50mm