3 The diagram shows a triangle \(A B C\).
The size of angle \(A\) is \(63 ^ { \circ }\), and the lengths of \(A B\) and \(A C\) are 7.4 m and 5.26 m respectively.
- Calculate the area of triangle \(A B C\), giving your answer in \(\mathrm { m } ^ { 2 }\) to three significant figures.
- Show that the length of \(B C\) is 6.86 m , correct to three significant figures.
- Find the value of \(\sin \boldsymbol { B }\) to two significant figures.