Answer: Easily A.
Step-by-step explanation: All you have to do is look at the power of the tens. The one that is the least is A. Since none of the other choices are equal to or less than 10^7, A is your answer. In scientific notation, you almost always look at the 10^x first.
For every side you just add 90 to your equation. so #4 would be 360-125-125-55=(55)
See the picture to better understand the problem
we know that
in the triangle ABC
∠A+∠B+∠C=180°
find ∠C
∠C=180-[80+65]------> ∠C=35°
Applying the law of sines
AB/sin C=CB/sin A
solve for CB
CB=AB*sin A/sin C-----> CB=45*sin 65/sin 35-----> CB=71.10 ft
the answer is<span>
the distance from person B to the top of the hill is 71.10 feet</span>