I think the answer is B but i could be wrong
-14+3/2b-(1+2/8b), then take out the blanket become -14+3/2b-1-2/8b , get 5/4b-15=0 so 5/4b=15 ,get b=15×4÷5. b=12
<h3>Key points :-</h3>
᪥ The formula to find the 31st term is : 
᪥ In the formula, 
represents the first term of the sequence.
᪥ 
is the number of terms, In our case n is 31.
᪥ 
is the common difference between the terms, In our case d is 4.
<em>Detailed Solution is attached</em>᭄
Answer:
RS=13
Step-by-step explanation:
RS+ST=RT
2w+1+w-1=18
3w=18
w=6
RS= 2w+1= 2(6)+1= 12+1= 13
