Math Help Forum: Bearings/trigonometry.

9) The following diagram shows part of a survey of a level plot of land. Where an angle is shown at a corner point, it gives the bearing of this point from the survey point O. Some edge lengths are known as shown.
a) Find the exact values of angles
i) AOB
ii) BOC
iii) COD
b) Use Heron's formula to find the area of the triangle AOE, correct to the nearest square metre.
c) Find the angle OE, correct to one tenth of a degree.
d) Find the true bearing of point E from O, correct to one tenth of a degree.
e) To the nearest degree, angle OBC is 64 degrees. Use this infromation to find to the nearest metre,
i) the distance from O to B
ii) the perimeter of the plot of land.

I know what the answers are! This is not homework and I am not cheating. If anyone could show complete working out that would be appreciated! Any altruism displayed in this thread will be thanked and I will increase your reputation!

Normally, would you have to show working out for these questions? For Heron's formula probably yes but what about all others?

I also don't know how to use Heron's formula above but I got the answer.

The distance between point A and point E is actually 310 m NOT 350 m! I'm so sorry for the incorrect value displayed.
Anyway, I've done most of this question and now just need help with the parts:
9)e)(i) and (ii)
Any help with these will be appreciated! Please help me somebody! It's not even that difficult; I just what to check my answers.

The answers are meant to be:
e(i) 368 m and (ii)2 488 m

EDIT: Could somebody also show complete working out for Heron's formula? Please anyone? My life depends on it! Please help me someone, just this once. I thought this site was meant for helping people. I need help!