Before the law came into force, start-ups could only raise money from qualified investors, and everyone was eligible to become a start-up investor after the jobs bill came into force. Interest determines the regularity of prescriptive (interest this qualitative rules will determine the amount of the rules), the amount of interest depends on profit, interest rate depends on the average profit margin. Marx further pointed out that, between average profit margin and zero, interest rate depends on two factors: one is profit margin; The second is the proportion of total profits allocated between lenders and borrowers. The "fish-type duck tail" model partially overcomes the lift of the air when the car is traveling at high speed, but it does not fundamentally solve the problem of lift of the fish. After a lot of exploration and experimentation, the designer finally found a new type of model - wedge. This type of vehicle is to tilt the body forward downward, and the back of the body is as straight as a knife, which can effectively overcome lift.