[填空题]
Farmer Jimmy bought 50 g7v(d7 tjh7p1k3iimg n* jy rcbw1j23toats and brought th)5b-ahduy -.p 4ip ilnl szblgd68-5ag k.uv -em to his farm. He determined that 10 of these new goats have a viral disease. The total number of gl.yh-6saallzg--8-iugp5b u vib. pd nk 54d)oats on Jimmy's farm is now 600.
The spread of the viral disease on Jimmy's farm is modelled by the logistic function
S(d)=$\frac{M}{1+Ce^{-kd}}$,where S(d) is the number of infected goats after d epidemic days.
1.(1)Write down the value of M. M =
(2)Find the value of C. C =
2.Given that quarter of the goats are infected after 12 days, find the value of k, giving your answer correct to 4 significant figures. k ≈
3.Find the number of days it takes for 90% of the goats to get infected. d ≈ days
4.Draw the graph of y=S(d) on the axes below, indicating clearly the point of inflexion and any asymptotes.