$1.$ Sumitomo Bank's risk manager has estimated that the DEARs of two of its major assets in its trading portfolio, foreign exchange and bonds, are $-$$$150,000$ and $-$$$250,000,$ respectively.

$-$ What is the total DEAR of Sumitomo's trading portfolio if the correlation among assets is assumed to be $0\mathrm{.}80?$

$-$ What is the total DEAR of Sumitomo's trading portfolio if the correlation among assets is assumed to be $0\mathrm{.}0?$

$-$ What is the $10-$day VAR of Sumitomo's trading portfolio if the correlation among assets is assumed to be $-1\mathrm{.}0?$

$-$ What is the total DEAR of Sumitomo's trading portfolio if the correlations among assets are ignored?