Solution: (1) ∫ p =-1100 (x-60)? When +4 1∴x=60, the maximum P is 4 1 ∴5 years, and the maximum profit is 41* 5 = 2.05 million yuan.

(2) Profits of the previous two years; 2 * [-1100 (50-60) 2+41]-100 * 2 =-200,000 yuan.

In the last three years, if the local investment is X million yuan, then the foreign investment is (100-x) X million yuan. Annual profit:

- 1/ 100(x-60)^2+4 1-99/ 100x^2+294/5x+ 160=-x^2+60x+ 165=-(x-30)^2+ 1065

When ∴x=30, the annual maximum profit is10.65 million yuan.

∴ Maximum profit in five years:1065 * 3-20 =11.75 million yuan.

(3)∵ 1 175 >205

This scheme is of great practical value.