点I为△ABC的内心,AI的延长线交△ABC的外接圆于D,以D为圆心,DI为半径画弧,是否经过点B与点C?说明理由.
证明:连接BI,
∵I是△ABC的内心,
∴∠BAD=∠DAC,∠ABI=∠CBI,
∴BD∧=CD∧
—Why do you look so tired?—Because we ________ for three hours without stopping.
____ Al+____MnO2=____Al2O3+____Mn该反应属于基本反应类型中的____反应,在反应中,MnO2被____,Al是____剂.