There is no way to tell because you have not given any details about the camera.
8.1MP has nothing to do with how many pictures the camera can save, it all depends on the memory type and how much memory you have for the camera. It also depends on how you store - high or low res JPEGs, or RAW etc. The storage is in the memory device, SD card, CF card, Memory Stick etc, so its capacity, typically 1 or 2 gigabytes or more, has to be counted. In a 1 gigabyte card you could store from less than 100 to several thousand pics.
22 gals.
5 QTS. with a new filter.
Depends, on if you are loading short, long or long rifle.
Now let's do some math... 4gb = 4x1024mb = 4096mb 4gb / 50mb = 4096mb / 50mb = 81.92 This means the 4gb card will hold 'bout 81 pictures. If you ever need to know while on the go, you can round off a gig to 1000mb to give you an approximate answer to make the math easier.
most starters have 3 ,but then again this is a 81 I would say 4
81 feet
81 81
.81 is how many hours
27 threes are in 81
1 goes into 81 81 times.
One: 81 squared = 81^2 = 6561
81 has 5 factors: 1, 3, 9, 27, and 81.