For each of the following pairs of polymers, decide whether or not it is possible to determine whether one polymer has a higher melting temperature than other. If it is possible, then from the pull-down menu select that polymer having the higher melting temperature. If it is not possible to decide, then select "not possible" from the pull-down menu.

(a) Branched polyethylene having a number-average molecular weight of 850,000 g/mol; linear polyethylene having a number-average molecular weight of 850,000 g/mol.

1- branched polyethylenenot

2- possible

3- linear polyethylene

(b) Polytetrafluoroethylene having a density of 2.14 g/cm3 and weight-average molecular weight of 600,000 g/mol; PTFE having a density of 2.20 g/cm3 and a weight-average molecular weight of 600,000 g/mol.

`1-PTFE

2-polytetrafluoroethylene

3-not possible

(c) Linear and syndiotactic poly(vinyl chloride) having a number-average molecular weight of 500,000 g/mol; linear polyethylene having a number-average molecular weight of 225,000 g/mol.

1-linear and syndiotactic poly(vinyl chloride)

2-not possible

3-linear polyethylene

(d) Linear and syndiotactic polypropylene having a weight-average molecular weight of 500,000 g/mol; linear and atactic polypropylene having a weight-average molecular weight of 750,000 g/mol.

1-linear and syndiotactic polypropylene

2-linear and atactic polypropylene

3-not possible