3. The geographical environment of a certain area is remote, severely restricting economic development. A certain local specialty can only be sold locally, and for every million yuan invested by the local government, the profit obtained is $P=-\frac{1}{160}(x-40)^{2}+$ 10 (million yuan). To comply with development policies, the local government, in formulating a ten-year economic development plan, plans to develop this specialty product. The special fiscal allocation for investment in this project is 60 million yuan annually, both before and after development. If the product is to be developed, 30 million yuan must be allocated from the 60 million yuan special fund each year for the first 5 years to build a road, which will take 5 years to complete. After the road is completed, the specialty product can be sold elsewhere, and for every million yuan invested, the profit will be $Q=-\frac{159}{160}(60-x)^{2}+$ $\frac{119}{2}(60-x)$ (million yuan). From the perspective of total profit over ten years, is there any value in developing this project?
3. (1) If the investment environment remains unchanged, from $P=-\frac{1}{160}(x-40)^{2}+10$, we know that when $x=40$, $P_{\text {max }}=10$. That is, by investing 400,000 yuan out of the 600,000 yuan special fund each year, a maximum profit of 100,000 yuan can be obtained. Therefore, the maximum total profit over ten years is $W=10 \times 10=100$ (ten thousand yuan);
(2) If the product is developed, only 300,000 yuan can be used for investment in the first 5 years, and $P=-\frac{1}{160}(x-40)^{2}+10$ is increasing on $(0,30]$, so when $x=30$, $P_{\text {max }}=\frac{75}{8}$, and the total profit for the first 5 years is $W_{1}=\frac{75}{8} \times 5=\frac{375}{8}$. Suppose after 5 years, $x$ ten thousand yuan is used for local sales investment, and $(60-x)$ ten thousand yuan is used for out-of-town sales investment, then the total profit is $W_{2}=\left[-\frac{1}{160}(x-40)^{2}+10\right] 5+\left[-\frac{159}{160} x^{2}+\frac{119}{2} x\right] 5=5\left[-(x-30)^{2}+900\right]$. When $x=30$, $\left(W_{2}\right)_{\text {max }}=4500$, so the maximum total profit over ten years is $\frac{375}{8}+4500>100$. Therefore, the project has great development value.