Two objects of masses $m_1=9\mathrm{.}7kg$ and $m_2,$ connected by a thin wire $(m_{\text{w}\text{i}\text{r}\text{e}}=0kg),$ are

attached to a system of two pulleys as shown in the figure. What is the mass $m_2$ knowing

that $a=90$ and the two masses do not move?

Select one:

a$.4\mathrm{.}96kg$

b$.5\mathrm{.}71kg$

c$.6\mathrm{.}24kg$

d$.6\mathrm{.}86kg$