The case supports power supplies up to 290 mm in length with only one 3.5" drive installed. With both, the max length would be 200-161 mm, depending on where you decide to install them.
As seen in the picture above, the length differs compared to the maximum length. The reason for this is to accommodate cabling.
These trays can support 1x 3.5" drive and 1x 2.5" drive at the same time:
In combination with the 2x dedicated 2.5" brackets in the case, you can install 2x 3.5" drives, and 4x 2.5" drives at the same time.