求角的度数.(如图)∠1=45°,∠2= 度,∠3= 度,∠4= 度,∠5= 度.
:8==0.25= %=5÷ .
÷15=3: =12/ =0.6= %
=20× =12÷15= %= 折= (填小数)= (填成数)
0.375= : == %.
2÷ ==0.4= %= (成数)