1. 度、分、秒转化：
(1)$57.32^{\circ }=$
(3)$12^{\circ }18'=$
(1)$57.32^{\circ }=$
57
$^{\circ }$19
$'$12
$''$； (2)$27^{\circ }14'24''=$27.24
$^{\circ }$；(3)$12^{\circ }18'=$
12.3
$^{\circ }$； (4)$6000''=$100
$'=$$\frac{5}{3}$
$^{\circ }$。答案：(1)57 19 12 (2)27.24 (3)12.3 (4)100 $\frac{5}{3}$
2. 计算：
(1)$42^{\circ }48'+36^{\circ }25'$； (2)$18^{\circ }20'+6^{\circ }30'$；
(3)$180^{\circ }-48^{\circ }39'40''$； (4)$38^{\circ }49'× 3$；
(5)$33^{\circ }15'16''× 5$； (6)$180^{\circ }÷ 8$；
(7)$56^{\circ }17'+12^{\circ }45'-16^{\circ }21'$； (8)$131^{\circ }28'-51^{\circ }32'15''$；
(9)$58^{\circ }38'27''+47^{\circ }42'40''$； (10)$34^{\circ }25'× 3+35^{\circ }42'$。
(1)$42^{\circ }48'+36^{\circ }25'$； (2)$18^{\circ }20'+6^{\circ }30'$；
(3)$180^{\circ }-48^{\circ }39'40''$； (4)$38^{\circ }49'× 3$；
(5)$33^{\circ }15'16''× 5$； (6)$180^{\circ }÷ 8$；
(7)$56^{\circ }17'+12^{\circ }45'-16^{\circ }21'$； (8)$131^{\circ }28'-51^{\circ }32'15''$；
(9)$58^{\circ }38'27''+47^{\circ }42'40''$； (10)$34^{\circ }25'× 3+35^{\circ }42'$。
答案：(1)79°13′ (2)24°50′ (3)131°20′20″ (4)116°27′(5)166°16′20″ (6)22.5° (7)52°41′ (8)79°55′45″(9)106°21′7″ (10)138°57′
解析：
(1) $42^{\circ}48' + 36^{\circ}25' = 78^{\circ}73' = 79^{\circ}13'$
(2) $18^{\circ}20' + 6^{\circ}30' = 24^{\circ}50'$
(3) $180^{\circ} - 48^{\circ}39'40'' = 179^{\circ}59'60'' - 48^{\circ}39'40'' = 131^{\circ}20'20''$
(4) $38^{\circ}49' × 3 = 114^{\circ}147' = 116^{\circ}27'$
(5) $33^{\circ}15'16'' × 5 = 165^{\circ}75'80'' = 166^{\circ}16'20''$
(6) $180^{\circ} ÷ 8 = 22.5^{\circ}$
(7) $56^{\circ}17' + 12^{\circ}45' - 16^{\circ}21' = 68^{\circ}62' - 16^{\circ}21' = 52^{\circ}41'$
(8) $131^{\circ}28' - 51^{\circ}32'15'' = 130^{\circ}87'60'' - 51^{\circ}32'15'' = 79^{\circ}55'45''$
(9) $58^{\circ}38'27'' + 47^{\circ}42'40'' = 105^{\circ}80'67'' = 106^{\circ}21'7''$
(10) $34^{\circ}25' × 3 + 35^{\circ}42' = 102^{\circ}75' + 35^{\circ}42' = 137^{\circ}117' = 138^{\circ}57'$
(2) $18^{\circ}20' + 6^{\circ}30' = 24^{\circ}50'$
(3) $180^{\circ} - 48^{\circ}39'40'' = 179^{\circ}59'60'' - 48^{\circ}39'40'' = 131^{\circ}20'20''$
(4) $38^{\circ}49' × 3 = 114^{\circ}147' = 116^{\circ}27'$
(5) $33^{\circ}15'16'' × 5 = 165^{\circ}75'80'' = 166^{\circ}16'20''$
(6) $180^{\circ} ÷ 8 = 22.5^{\circ}$
(7) $56^{\circ}17' + 12^{\circ}45' - 16^{\circ}21' = 68^{\circ}62' - 16^{\circ}21' = 52^{\circ}41'$
(8) $131^{\circ}28' - 51^{\circ}32'15'' = 130^{\circ}87'60'' - 51^{\circ}32'15'' = 79^{\circ}55'45''$
(9) $58^{\circ}38'27'' + 47^{\circ}42'40'' = 105^{\circ}80'67'' = 106^{\circ}21'7''$
(10) $34^{\circ}25' × 3 + 35^{\circ}42' = 102^{\circ}75' + 35^{\circ}42' = 137^{\circ}117' = 138^{\circ}57'$