Custom Data Validation

I am trying to apply custom data validation for two cells

The first is data validation in cell B6. The only valid entries should be in mulitples of 100 (e.g. 100, 200, 300, .... etc).

The second cell is B12. The only valid enteries should be any number above 100 and not = 100, 200, 300, .... etc).

I tried using following formula in data validation for cell B6 but no luck. Couldn't figure out what to use for cell B12

=mod(B6,100)