Answer:
C
Explanation:
Let p represent the cost for one pound of peanuts and let c represent the cost for one pound of cashews.
Two pounds of peanuts and three pounds of cashews cost $17.50. So:

Five pounds of peanuts and two pounds of cashews cost $19.00. So:

This yields a system of equations.
We can solve this using elimination. We can multiply the first equation by -5, and the second by 2. Therefore:

Multiply:

And:

Multiply:

Now, we can add the two equations together:

Combine like terms:

Therefore:

So, a pound of cashews costs $4.50.
Our answer is C.
Notes:
To solve for the cost for peanuts, we can use the first (or second equation) again:

Substitute:

Solve for p:

So, a pound of peanutes cost $2.00.