干木柴的热值是1.3×l07J/kg，要放出3.9×107J的热量，需要完全燃烧 ______kg的干木柴。
3
—I failed again. I wish I _________ harder.
—But you _________.
A．had worked; hadn’t
B．worked; don’t
C．had worked; didn’t
D．worked; didn’t
红墙巷因学宫的红墙得名，请问是何学宫？
