Explain the relationship between multiplying and dividing by 10, 100 and 1000 and moving the decimal point to the left or to the right

Examples:
1) Multiplying (for 10 , 100, 1000  always moving to the right)
    12.45*10=124.5*10         Moving to the right (1 "step")
    37.321*100=3732.1         Moving to the right (2 "steps")
    1.56789*1000=15678.9   Moving to the right (3 "steps")
2) Dividing (for 10 , 100, 1000  always moving to the left)
    56.89/10= 5.689                      Moving to the left (1 "step")
    234.98/100=2.3498                 Moving to the left (2 "steps")
    78956.67/1000=78.95667       Moving to the left (3 "steps")

Hello! i hope this
since the cosine is the ratio of the adjacent side to the hypotenuse, you can see that cos 60° = ½. answer. according to the property of cofunctions (topic 3), sin 30° is equal to cos 60°. sin 30° = ½.