How many are correct statements
(a) Neopentyl bromide is example for primary alkyl halide
(b) Secondary butyl bromide exhibits optical isomerism
(c) Boling point order  ${\mathrm{CH}}_3\mathrm{I}>{\mathrm{CH}}_3\mathrm{Br}>{\mathrm{CH}}_3\mathrm{Cl}>{\mathrm{CH}}_3\mathrm{F}$
(d) Boling point order n-butyl bromide > secondary butyl bromide > tertiary butyl bromide
(e) For fire extinguisher  pyrene the value of dipole moment is zero debye
(f) Number of fluorine atoms present in monomer of Teflon is 4

All the statements are true.

How many are correct statements
(a) Neopentyl bromide is example for primary alkyl halide
(b) Secondary butyl bromide exhibits optical isomerism
(c) Boling point order  ${\mathrm{CH}}_3\mathrm{I}>{\mathrm{CH}}_3\mathrm{Br}>{\mathrm{CH}}_3\mathrm{Cl}>{\mathrm{CH}}_3\mathrm{F}$
(d) Boling point order n-butyl bromide > secondary butyl bromide > tertiary butyl bromide
(e) For fire extinguisher  pyrene the value of dipole moment is zero Debye
(f) Number of fluorine atoms present in monomer of