解:?$ (2)$?∵?$∠CAB = 60°,$??$AF $?平分
?$∠CAB,$?
∴?$∠FAP = 30°。$?
如圖,當?$∠AFP=∠FAP = 30°$?時,
?$∠APD=∠FAP+∠AFP = 30°+30°=60°;$?
如圖,當?$∠AFP=∠APF $?時,
∵?$∠FAP = 30°,$?
∴?$∠AFP=∠APF=\frac {1}{2}×(180°-30°) = 75°,$?
∴?$∠APD=∠FAP+∠AFP = 30°+75°=105°$?
如圖,當?$∠APF=∠FAP = 30°$?時,
?$∠APD = 180°-30°=150°。$?
綜上所述,?$∠APD$?的度數(shù)為?$60°$?或?$105°$?或?$150°。$?
?$ (3)∠FMN=∠FNM。$?
理由如下:∵?$∠FNM$?是?$\triangle BMN$?的一個外角,
∴?$∠FNM=∠B+∠BMN,$?
∵?$∠B = 30°,$?
∴?$∠FNM = 30°+∠BMN。$?
∵?$∠BMF $?是?$\triangle AFM$?的一個外角,
∴?$∠BMF=∠MAF+∠AFM,$?即
?$∠BMN+∠FMN=∠MAF+∠AFM,$?
又∵?$∠MAF = 30°,$??$∠AFM = 2∠BMN,$?
∴?$∠BMN+∠FMN = 30°+2∠BMN,$?
∴?$∠FMN = 30°+∠BMN,$?
∴?$∠FMN=∠FNM。$?