A. show that the ratios 10/20 and 30/60 form a proportion by finding a common multiplier.
b. show that the ratios in part (a) are equal by writing them in simplest form.

Step-by-step explanation:

(A) We need to show both fraction of same proportion.

Ratio 1:  

If we multiply by 3 at numerator and denominator

(B) Now we simplify both ration into simplest form

2. angles qrt and qst both measures 156 degrees.

step-by-step explanation:  

we have been given a diagram of a circle and we are told that measure of arc qvt is 156 degrees.  

we can see from our given diagram that angle qrt and angle qst subtends to arc qvt.

since we know that angles subtended by the same arc at the circumference are always equal.

by angle subtended by same arc theorem, measure of angle qrt and angle qst will be equal to the measure of arc qvt.

therefore, angles qrt and qst both measures 156 degrees and 2nd statement is the correct choice.

c) yes, because of asa or aas