5 is A, because it's the only number that is whole when square rooted.
6 is confusing because it only gives you one number per answer, unless you are to add the two distances together? Then it would be 7 because X's distance is +4 and Y's distance is +3
I do not have an answer for 7
8 is 3.7 (or C)
9 is an easy one. Find out what the L and W is, and since it's a square we only need to find one of them. We square root the area and we are given 14.96662955, if rounded we get 15. So the answer is A
10 I don't understand the "estimate" for a square root number, I was not taught that.
Answer: Percentage change in quantity would decrease by 12.5%.
Step-by-step explanation:
Since we have given that
Price elasticity of demand = -0.8
Price of each unit = $100
After change, price of each unit becomes = $110
% change in quantity would be

As we know the relation between price, quantity and elasticity.

Hence, Percentage change in quantity would decrease by 12.5%.
No they are not, 6/8 could also be represented as 3/4. Therefore they are not equivalent. You would divide each side by the factor they have in common such as 2.
30% percent is what they marked up
Answer: Expression
Hope this helps :)