[填空题]
An elephant raised in a wilv +:x eg:vf8hfdlik + gvm4eh5wfx3w .fn(fe sanctuary. Her height, H, in metres, is modelled by the 3 vnfhxgw( .kf4w5m+elogistic function
H(t)=$\frac{2.5}{1+1.5e^{-0.25t}}$,
where t is the number of years that have passed since her birth.
1.Find the elephant's height:
(1)when she was born; H = m
(2)on her 55th birthday. H ≈ m
The elephant's height approaches a limit of M metres as she ages.
2.Write down the value of M. M =
The elephant reaches a height of 22 m before her $n$th birthday.
3.Find the smallest value of n. n =
