<h2>
Answer:</h2>

<h2>
Step-by-step explanation:</h2>
This is a square pyramid because it's a solid having a square base. The point up the pyramid is called the apex and is directly above the middle of the square base. The surface area of a solid is the total area of its outer surface. If we unfold this pyramid, we'll get one square and four identical triangles. So the surface are can be calculated as follows:

FOR THE SQUARE:
FOR THE TRIANGLE:

Finally:

Answer:the 3rd one
Step-by-step explanation:
285% is same as 285/100 which equal 2.85
Then 2.85 x 171 = 487.35
Answer: 487.35
Answer:
Look at picture answer is 2500
Step-by-step explanation:
Answer:
40
Step-by-step explanation:
why ? because the total angle measure in triangle is 180degree so we have a right angled triangle so 90+50 = 140
180-140 = 40
hope it's correct