Reset button to set all data to original settings

I have 5 sets of data ranging as follows on a worksheet named DATA1. The data is found at M2:P21, M25:P44, M48:67, M71:P90 and M94:P113. I would like to have a reset button on a sheet named MONDAY that, when pushed, resets all of the aforementioned cells to a status of "1". Can you assist me with this problem? I am very new to VBA and would need explicit instructions on where to place the VBA instructions for it to operate properly. Also, can it be programmed with a warning about "Are You Sure You Wish To Reset All Data?" Thanks in advance for your help.

I had to make a few small changes...but it worked like a charm! Thanks so much for the guidance as well.