3- the opening value of a stock index on the first day of trading from 1994 to 2010 can be modeled using the following polynomial: N(t)=11.8690t^3+20.3119t^2+22.0273t+757.2156N(t)=11.8690t3+20.3119t2+ 22.0273t+757.2156 where tt is time in years since 1994 What is the y-intercept and what does this tell you in practical terms?