The standard deviation of the market$-$index portfolio is $20\%.$ Stock A has a beta of $1\mathrm{.}75$ and a residual standard deviation of $30\%.$

Required:

a$.$ Calculate the total variance for an increase of $0\mathrm{.}25$ in its beta. $($Do not round intermediate calculations.$)$

Total variance $,0\mathrm{.}2500$

b$.$ Calculate the total variance for an increase of $30$ percentage points in its residual standard deviation. $($Do not round intermediate calculations.$)$

Total variance