Answer:
6.13
Step-by-step explanation:
Using Sine Law we know that

Using your figure let's assign sides and angles:
A=? B = 60° C = 70°
a = 5 b = ? c = x
If we put that into our formula:

Notice that we have too many unknowns. We need to complete at least one ratio to do this, so how do we do this?
Notice we have 2 angles given, so we solve for the third angle. The sum of all angles in any triangle is always 180°
∠A + ∠B + ∠C= 180°
∠A + 60° + 70° = 180°
∠A + 130° = 180°
∠A = 180° - 130°
∠A = 50°
Now we can use this to solve for x.

So the closest answer would be 6.13