题目

When we talk about a library, we may think of shelves and shelves lined with books. But a new library set to open this fall in Texas won’t have any books ---- at least not the kind you can leaf through.. There will be 10,000 digital books available for loan（借出）in the BiblioTech library in Bexar County, Texas. About 1.7 million county residents will be able to check out the books online without leaving their homes. The library will also provide 100 e-readers for people to borrow. In the library, people can work, study and access the Internet using dozens of computer stations.如图，四棱锥S-ABCD的底面为正方形，SD⊥底面ABCD，则下列结论中不正确的是（ ）A．AC⊥SBB．AB∥平面SCDC．SA与平面SBD所成的角等于SC与平面SBD所成的角D．AB与SC所成的角等于DC与SA所成的角