Easy Puzzles 

Workings

Hint
There are lots of vowels.

Answer
A.

This is the vowels AEIOU intermingled with the reverse UOIEA.

Workings

Hint
One possible answer begins with the letter A.

Answer
ark: bark, dark, market, parking, shark.

or:

ill: bill, dill, millet, pilling, shill.

Workings

Hint
Adults have fewer bones than children.

Answer
Days in a year.

There are usually around 206 bones in an adult human body, and 365 or 366 days in a year.

Workings

Hint
The missing word is five letters long.

Answer
State.

restate devastate reinstate overstate interstate understate.