What is the meaning of this rebus?

cannon
ordnance
artillery
torpedo

Each statement describes two words that when fused together create a new unrelated word (not a compound word). The clues do not necessarily indicate in which order the two words are attached. Example: This is the oldness of a tablet (pill + age = pillage).

1) This is a canine's mother.
2) This is currently not there.
3) This is when pain is required.
4) This is a long time for a boar.

Below is a list of five countries, all with the vowels removed. Can you name them?

1) LGR
2) CRT
3) THP
4) CDR
5) ND

Remove a letter from each of the words below and rearrange the remaining letters to form new words. The 10 words will all fall into a certain category. For example, given the words DEAR, ANGRY, and RENEGE, you could drop the "A" in DEAR to get RED, drop the "N" in ANGRY to get GRAY, and drop an "E" in RENEGE to get GREEN. These would all fall into the category of "Colors".

If you're stuck, the hint will name the category. The tough part is ...