0 24 H in a D
24 HOURS IN A DAY
1 5 to 7 C of the W
5 to 7 continents of the world
2 1 O G E 4 Y
1 Olympic games every 4 years
3 208 to 214 B in a H B
208 to 214 bones in a human body
4 2 M a P
2 makes a pair
5 6 S of a C
6 sides of a cube
6 8 B in a B
8 bits in a byte
7 1.6 K in a M
1.6 kilometers in a mile
8 4 W of a C
4 wheels of a car
9 8 L on a S
8 legs on a spider
10 191 U N M S
191 united nations member states
11 2 D in a W
2 days in a weekend
12 168 H in a W
168 hours in a week
13 101 D
101 dalmatians
14 7 D S
7 deadly sins
15 9 P in the S S
9 planets in the solar system
16 17 is a P N
17 is a prime number
17 9 M of P
9 months of pregnancy
18 17 S in a H P
17 syllables in a haiku poem
19 1 7 S H in the W
1 7 star hotel in the world
20 52 W K on a P
52 white keys on a piano
21 21 Q S F
21 questions so far
22 4 H of the A
4 horsemen of the apocalypse
23 115 K C E
115 known chemical elements
24 6 S W M (S F)
6 Star Wars Movies (So Far)

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).