Random Puzzles 

Workings

Hint
The words begin with the letters R, S, T.

Answer
RADII, SKIING, TAXIING.

You could also have GENII.

Workings

Hint
This is a very common sequence.

Answer
A.

August, from initial letters of the months of the year.

Workings

Hint
Is a million grains of sand a heap?

Answer
We can probably agree on two things:

A million grains of sand is a heap.
If we remove one grain of sand from this heap, we will still have a heap.
We can now keep repeating (2) until we only have a single grain of sand remaining.

Is this a heap? Clearly not. But what went wrong with our thinking?

This is called the Sorites paradox (soros being Greek for "heap") and is a classic paradox that has no real answer.

Both (1) and (2) are true, and we can indeed keep removing one grain of sand until we have a single grain remaining. If we remove one more grain, we're left with nothing, is this still a heap?

When does the heap become a non-heap?

Workings

Hint
The of words are all fruits.

Answer
Banana, apple, pear, and mango.