Random Puzzles 

Workings

Hint
Look at the letter positions in the alphabet.

Answer
R.

If you take the alphabetic positions of each letter in a row, the total is always 56.

Double-Checking
Y + G + W + A = 25 +  7 + 23 +  1 = 56
K + L + R + O = 11 + 12 + 18 + 15 = 56
Z + J + P + D = 26 + 10 + 16 +  4 = 56
V + F + T + H = 22 +  6 + 20 +  8 = 56

Workings

Answer
293 031: these are the numbers 20, 21, 22, 23 etc grouped into three digits.

Workings

Hint
The second word is CORD.

Answer
COLD, CORD, WORD, WARD, WARM

or

COLD, CORD, WORD, WORM, WARM

or

COLD, CORD, CARD, WARD, WARM.

Workings

Hint
Where do the letters of STOP occur in SAFE, STAY, SOON, SKIP?

Answer
POST.

Using the first letter of the first word, the second letter of the second word, etc.