The standard deviation of the market$-$index portfolio is $15\%.$ Stock A has a beta of $2\mathrm{.}20$ and a residual standard

deviation of $25\%.$

Required:

a$.$ Calculate the total variance for an increase of $0\mathrm{.}20$ in its beta. $($Do not round intermediate calculations.$)$

Answer is complete but not entirely correct.

b$.$ Calculate the total variance for an increase of $3$ percentage points in its residual standard deviation. $($Do not round

intermediate calculations.$)$

Answer is complete but not entirely correct.

$25\mathrm{.}6100$