Capital gains on Unit build on subdivided land

Hi
I need some advice please
I have recently got a permit to build a unit on back of my house, a corner block. I will subdivide the land. I had the property for 2.5years
My questions are

1. What will be the capital gain tax if i sell the subdivided land. Is it going to applicable of 50% of the capital gain because i had the house for 2.5years or will it be charged on fll capital gain

2. If i build a unit on the block. Will the capital gain tax be charge on 50% of capital gain or full capital gain considering i had the original house for 2.5 years

thanks for the advice

Mezi