Arithmetic in the mathematical angle of senior one: [1]90 degrees -28 degrees 35 minutes 40 seconds [2]23 degrees 30 minutes 24 seconds times 8 [3]40 degrees 35 minutes divided by 3[ I want the process] I'll tell you the method, and I'll do the math myself. One degree angle =60 minutes =3600 seconds.

[1]90 degrees -28 degrees 35 minutes 40 seconds =89 degrees 59 minutes 60 seconds -28 degrees 35 minutes 40 seconds

[2]23 degrees, 30 minutes and 24 seconds multiplied by 8 =23 degrees *8+30 minutes *8+24 seconds *8 and then convert the minutes and seconds forward.

[3]40 degrees 35 minutes divided by 3=40 degrees 33 minutes 120 seconds divided by 3

In short, you have to calculate the minutes and seconds of the formula first, and then think about whether to convert it forward or backward. Just make a few more.