Margin After Hours and Pre Market

Could someone explain to me whether or not interest is charged when buying/selling stocks on margin in the following three scenarios:

1. Buying at the open of after hours (~4:05pm) and selling at the close of after hours (~7:55pm).

2. Buying at the open of pre-market hours (~4:05am) and selling at the close of pre-market (~9:25am).

3. Buying at the open of after hours (~4:05pm) and selling at the close of pre-market (~9:25am).

Thanks in advance!