Give the `IUPAC` names for the following:
(i) `CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C )-C-=CH`
(ii) `CH_(2) = CH - CH_(2) - C -= CH`
(iii) `CH_(3)C-=C CH_(2)underset(CH_(3))underset(|)overset(CH_(3))overset(|)(C )-CH_(2)CH_(3)`
(iv) `(CH_(3))_(3)C - C -= C(CH_(3))_(3)`
Strategy: Alkynes are named in much the same way as alkanes. Unbranched alkynes are named by replacing the -ane of the name of the correponding alkane with the ending -yne. The chain is numbered fo as to give the `C` atoms of the triple bond the lower possible numbers. The lower number of the two `C` atoms of the triple bond is used to designate the location of the triple bond. The locationa of side chains of branched alkynes are also indicated with lower numbers.

Explanation

(i) `3,3`-Dimethylbut-`1`-yne
(ii) Pent-`1`-en-`4`-yne (not pent-`4`-en-`1`-yne)
(iii) `5,5`-Dimethylhept-`2`-yne
(iv) `2,2,5,5`-Tetramethylhex-`3`-yne