Answer:
Equivalent ratios: we can that the first ratio is equivalent to the second,  then third ratio is equivalent to the forth.  
Ratio: 1: 2 Value of the Ratio:  1/2
Ratio: 5: 10 Value of the Ratio:  1/2
Ratio: 6: 16 Value of the Ratio:  3/8 
Ratio: 12: 32 Value of the Ratio: 3/8
We notice that if the values are equivalent the ratios are equivalent
Step-by-step explanation:
Equivalent ratios: 
To get if ratios are equivalent we look for the constant between ratios 
a.Ratio: 1: 2  and Ratio: 5: 10  
We apply the method of comparing the first term of both ratios ,  and the second term of both ratios.  We see the constant is 5 ( 1/5 is equal to 2/10)
We do the same with third and forth ratio 
Ratio: 6: 16 compare to Ratio: 12: 32
6/12 is equal to 16/32 the constant is 2 
<u>So,  we can that the first ratio is equivalent to the second,  then, third ratio is equivalent to the forth.  </u>
Value of the Ratio:  The value is a ratio written as a fraction. 
Ratio: 1: 2 Value of the Ratio:  1/2
Ratio: 5: 10 Value of the Ratio:  5/10 if we divide both sides by 5,  we can say  Value of the Ratio:  1/2
Ratio: 6: 16 Value of the Ratio:  6/16 if we divide both sides by 2,  we can say the value is 3/ 8
Ratio: 12: 32 Value of the Ratio: 12/32 if we divide both sides by 4,  we can say the value is 3/ 8
<u>If the values are equivalent the ratios are equivalent.</u>