Answer:
1). Option (2)
2). Option (4)
Step-by-step explanation:
1). Formula to evaluate the actual cost 'a' of an item with original price 'm' and a discount coupon for 'n' dollars applied will be,
a = m - n
n = m - a
Therefore, expression (2) will be the answer.
2). Deon ride a 15 mi bicycle trail.
Average speed of the trail is = 20 miles per hour
From the formula,
Speed = 
Time = 
=
hours
Therefore, Option (4) will be the answer.
Answer: 0.89z
Think of it like 100% - 11% = 89%
You save 11%, so you need to pay the remaining 89%
Taking 89% of z then leads to 0.89z
So that's why z - 0.11z = 0.89z
I really don't know just say its o