At the top of the grinder, just below the handle that you squeeze to grind the salt/pepper, there is a hinged opening on each side labeled "s" and "p" . I used a finger nail on the top seam of that door to pop it open. You can then pour your salt and pepper in and snap them shut.
The factors of 921 are: 1, 3, 307, 921
921 = 92100%
921 3,307
6459-921 what = 5538
1 x 921, 3 x 307, 307 x 3, 921 x 1 = 921
92134 ÷ 100 = 921 hundreds with a remainder of 34
921 = CMXXI
931 = 10 + 921
v - 921 is in its simplest form.
921
0.0033
921 in Roman numerals is CMXXI.