Compare $M_x$ for a series of elastomers $($listed in the table below$)$ using two methods: $1)$ tensile

measurements and $2)$ calculated using known crosslink fractions. The stress of the elastomers

was measured at an extension of $100\%.$ The molecular weight of the polymer used to create

the elastomers was $225,000\frac{g}{m}ol(M_0=68\frac{g}{m}ol)$ and all elastomers had a density of $0\mathrm{.}92$

$\frac{g}{c}{m}^3.$ Discuss potential reasons for the discrepancies between $M_x$ determined from tensile

measurements and calculated using known crosslink fractions. $(1\mathrm{.}5$ points$)$