Select a starting material and a series of reagents necessary to synthesize this compound in as few steps as possible. Enter your selection as a number for the starting material, followed by the letters of the reagents, in the order that you wish to use them, i.e. 3abcf.

The  volume that  will  occupy  at STP  is  calculated   as  follows
by use  of ideal  gas  equation
that is  PV=nRT  where n  is  number of  moles  calculate  number of moles

n= PV/RT
p=0.75 atm
V=6.0  L
R = 0.0821  L.atm/k.mol
T=  35  +273= 308k
n=?

n=  (o.75  atm  x  6.0 L)/( 0.0821 L.atm/k.mol  x 308 k)=  0.178 moles

Agt  STP  1 mole=  22.4 L  what obout  0.178 moles

=  22.4  x0.178moles/ 1moles =3.98 L( answer C)