How present only two buttons on a tablet screen

My application has need of only two button with around 15 characters for each, on the main screen. The problem is the screen is large on tablet. How can I present these two button ?

Answer

Centered design, on top of each other both in landscape and portrait? Looks easy to use, but it really depends on context. I'm assuming the buttons are a group, and that's the basis of my design

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