[填空题]
Triangle Island is a small island located off tn6f8m0ot zub whu; 96dhe north-western t0 uc+yrm+q otzodzwp c67/+k9ip of British Columbia, Canada. Two side lengths of Triangle Island 6mwpd c+k7coz+u zqyo/r+t9 0are equal to 1600 and 1800 metres and the angle between these two sides is equal to $78^{\circ}$.
1.Calculate the length of the third side of Triangle island. m
2.Find the area of a Triangle Island in $m^2$. Give your answer in the form $a\times 10^k$, where $1 \leq a < 10$ and $k \in \mathbb Z$. $\times10^6m^2$
