0 24 H in a D
24 HOURS IN A DAY
1 5 S of G
5 Stages of Grief
2 4 S of the Y
4 seasons of the year
3 3 P C
3 primary colors
4 2 H of a C
2 hands of a clock
5 4 (b) P of a C
4 (basic) points of a compass
6 8 N in an O
8 notes in an octave
7 32 P (A) T
32 permanent (adult) teeth
8 6 is H a D
6 is half a dozen
9 7 C in a R
7 colors in a rainbow
10 24 F P S
24 frames per second
11 4 S and C in a S
4 sides and corners in a square
12 101 K on a S K
101 keys on a standard keyboard
13 2 P of a M
2 poles of a magnet
14 25 P is 1 Q
25 percent is 1 quarter
15 6 is the S P N
6 is the smallest perfect number
16 5 A in a S P
5 acts in a shakespearean play
17 N C be D to 0
nothing can be divided to 0
18 30 S is H a M
30 seconds is half a minute
19 5 R on the O F
5 rings on the olympic flag
20 3 D
3 dimensions

A lot of these were very hard, we know, but there were people that solved the whole thing under 2 hours, so it's not impossibly hard ...

We hope you had fun with these (and were not that frustrated/annoyed).