Answer:
eY is positive +0.1 therefore bagels are a normal good.
Step-by-step explanation:
Given data:
when, 10% rise in cheese price, 3% fall in bagels quantity observed
when, 10% rise in income, 1% fall in bagels quantity observed
from formula for cross price elasticity of demand, determine 

As, eAB is negative, bagels $ cream cheese are complements.
By formula for income elasticity of demand,
we find that
Since eYis positive, bagels are a normal good.
Well x=1 always unless it tells you other wise so 1+0.5 would equal 1.5 and so after that you keep adding so 1.5 + 0.5 equal 2 so you keep taking the previous answer and adding 0.5 to it
ΔABC ~ ΔADE
AC/AE = AB/AD
AC/(AC+15) = 8/18
18AC = 8(AC+15)
18AC = 8AC + 120
18AC - 8AC = 120
10AC = 120
AC = 120/10
AC = 12
1:B, 2:A, 3:D, 4:A
those are the answers
Extend means to increase, add length to it, ADD.
2.826
+ 1.46
--------------
4.286