ok im good at reaching high notes in music , however i crack on some high notes?

[BtotheG]

I was originally a bass but ive been appointed bass and tenor in some songs. problem is a few high notes i end up cracking my voice and i suck =/ is it possible to make it more smooth? and can one person go from bass to tenor?
btw im 17 ....

 

[Kayla]

All you can do is stretch your voice during
vocal warm ups (you can youtube different warmups if you need more).
It takes time, but it can be done.
Avoid drinking acidic or carbonated drinks and oily
foods aswell. And never drink really cold or hot water
before singing. Luke warm is the best.