finding p value

Here's what is given:
SE of .1
Average mean: 5.4 ft (100 penguins tested)
significance level: 5% (0.05)

find p-value and testis there is evidence that the average height of penguins is greater than 5 feet?

Heres what i did:

test stat: (5.4-5)/.1 = 4
p - value: Used calculator and got: 1 or 0 which both seem very very incorrect even if one of them were right.

What am i doing wrong?