What is the beta of a portfolio comprised of the following securities$?$

Stock Amount Invested Security Beta

A $ $5,0001\mathrm{.}64$

B $ $6,0001\mathrm{.}75$

C $ $8,5001\mathrm{.}00$

Multiple Choice

$1\mathrm{.}640$

$1\mathrm{.}750$

$1\mathrm{.}463$

$1\mathrm{.}395$

$1\mathrm{.}000$