I believe these are the answers.
A
i) (y=5) x=6
ii) (y = -1) x=0
iii) (y = -2) x = -1
B
i) (x = -4) y = -5
ii) (x=2) y=1
iii) (x=5) y=4
Sorry if these are wrong but I hope the help.
We are given our function as

For finding concavity , firstly we will find second derivative



now, we can find derivative again




now, we can know second derivative is undefined when denominator =0
so, we set denominator =0
and then we can solve for x


now, we can draw a number line and locate x=-4
and then we can find sign of second derivative on each intervals
so,
Concave downward interval:

Answer:
im so so so sorry, but i dont know(possibly because im only in 7th grade with a sucky teacher)
Step-by-step explanation: