题目

抛物线y=(x+2)2+3的顶点坐标是(    )             A. （－2，3）                      B. （2，3）                      C. （－2，－3）                      D. （2，－3） 答案： AWe have made up our minds to carry out the experiment, _____ great difficulties we may meet. A. however B. whatever C. wherever D. whenever