The purchase price of local sweet potatoes is about 4 cents per catty of fresh sweet potatoes. According to the calculation of 7 kg sweet potato processing 1 kg sweet potato powder, the cost of 1 kg sweet potato powder is 2.8 yuan, and 1 kg sweet potato powder can be processed into 1 kg vermicelli. The price of local pure sweet potato vermicelli is around 8- 10 yuan. That is to say, according to the lowest price of one catty in 8 yuan, the 2.8 yuan of seven catties of sweet potatoes is converted into 8 yuan money through processing. The annual salary of more than 200 thousand is not a problem. ?