Answer:
a) 1/27
b) 16
c) 1/8
Step-by-step explanation:
a) 
One of the properties of the exponents tells us that when we have a negative exponent we can express it in terms of its positive exponent by turning it into the denominator (and changing its sign), so we would have:

And now, solving for x = 9 we have:

b) 
This is already a positive rational exponent so we are just going to substitute the value of y = 8 into the expression

c) 
Using the same property we used in a) we have:

And now, solving for z = 16 we have:

Any kind of Triangle must have 180 degree of angle in total if it is not, then it is not a Triangle.
In short, Your Answer would be Zero
Hope this helps!
Answer:
16 cups of water
Step-by-step explanation:
You find this by dividing 28 by your ratio of flour to get 4, then multiplying the cups of water, 4, by 4 to get 16 cups of water
The answer to your question is 20/9