a. `(CH_(3))_(3) N`
b.
c. Degree unsaturation:
`((2 n_(C ) + 2) - n_(H))/(2) = (10 - 8)/(2) = 1^(@)`
`1^(@) D.U`. Suggests either unsturated alcohol or cyclic `3^(@)` alcohol four `C` atoms, `3^(@)` alcohol cannot be unsturated, so it is cyclic
f. `D.U. = 1^(@). 1D.U.` suggests unsaturated alcohol or cyclic `2^(@)` alchohol three `C` , `2^(@)` alcohol cannot be unsaturated, so itis cyclic.