Answer:
Ok, we know that the price, per pond of grapes, is $1.99.
Now the function that models the cost of grapes is:
C(x) = $1.99*x
Where x is the number of pounds that you buy.
Here we can assume two things:
1) The grapes are already in bags, so x can be only whole numbers, as x can take only whole numbers, the cost c(x) will be discrete because there are a lot of possible costs that are not accessible.
Then the domain is:
D: {0, 1, 2, 3, 4.....}
And the range is :
R: {0*$1.99. 1*$1.99, 2*$1.99, ...}
2)You can choose any amount of grapes that you want, and then the grapes are weighted when yo pay. (This has not really sense, but it is fun to analyze the problem in different ways)
Here the weight can take almost any value, because with individual grapes you can have almost any number of pounds.
But the unit that defines the total weight is the weight of a single grape.
Then if you have N grapes (and all of them weight almost the same, let's say M)
The total weight will e N*M
If you add one more grape, the weight is: (N + 1)*M
Then it is still discrete!
As we do not know the mean weight of a grape, we can not find the domain nor the range in this situation, so the one above is the one that we should consider the correct one.