$4.$ You have invested $$100,000$ in the stock of HSBC and $$200,000$ in the stock of Legend. Suppose the return of HSBC is $10\%$ over the last year, and the return of Legend in the

same year is $8\%,$ what is the return on your portfolio over the past year?

a$.6\mathrm{.}81\%$

b$.7\mathrm{.}10\%$

c$.7\mathrm{.}90$

d$.8\mathrm{.}17\%$

e$.8\mathrm{.}67\%$