word problem Trigonometry

Hello, me again! and I need ur help!

In summary octupus ride

one revolution=60 seconds

max 4m above ground

min 1 m above ground

h in metres above ground can be modelled by

h=asin (kt) +c where t=time in seconds

question?

what is the desired period of the fxn?

my answer: I just assumed its 60 seconds? am I right

Determin the value of K that results in the period desired

so for amplitude I got 3/2 and vertical translation 5/2

therefore:

h=3/2 sink (60) +5/2

im stuck. I have have no idea how to solve for K, since there is two varialble. any hints is appreciated!