It has been determined that the of producirig $x$ units of a certain item is $6 x+860$. The demand function is given by $p(x)=50-0.5 x$. Step 1 of 2 : Find the revenue function.

Step 1 ：The cost of producing \(x\) units of a certain item is given by the function \(C(x) = 6x + 860\). The demand function is given by \(p(x) = 50 - 0.5x\).

Step 2 ：The revenue function is the product of the price function and the quantity of items sold. In this case, the price function is \(p(x) = 50 - 0.5x\) and the quantity of items sold is \(x\).

Step 3 ：Therefore, the revenue function \(R(x)\) can be calculated as \(R(x) = x * p(x)\).

Step 4 ：Substituting the given price function into the revenue function, we get \(R(x) = x * (50 - 0.5x)\).

Step 5 ：Simplifying the above expression, we get the final revenue function as \(R(x) = 50x - 0.5x^2\).

Step 6 ：\(\boxed{R(x) = 50x - 0.5x^2}\) is the final answer.