Stats_linear combo ch6 REVIEW p1

E(l)

$$E(l)=1\ast 10+2\ast 10-3\ast 10=0$$

Find V(l)

$$V(l)=1\ast 4+4\ast 4+9\ast 4=4+16+36=56$$

cov(Y_1,Y_3)

$cov(Y_i,Y_j)=0$, for all i not equal to j by independence

$l\sim N({\mu }_l,{\sigma }_l)$

True, Since l is a linear combination of Normals l is normal