Peter has a rope, and he ties some knots, each using $10$-cm rope. He ties $25$ knots in total. After he ties the last knot, the knots divide the rope into pieces~ equally, and the length of each piece is $7$ cm. What is the length of the entire rope? 
选项为:A:$$425$$ cm  B:$$432$$ cm  C:$$456$$ cm  D:$$478$$ cm  E:$$480$$ cm  请回答其中一个选项.