It’s a little surprising that this question didn’t come up earlier. Unfortunately, there’s no intuitive way to understand why “the energy of the rest mass of an object is equal to the rest mass times the speed of light squared” (E=MC2). A complete derivation/proof includes a fair chunk of math (in the second half of this post), a decent understanding of relativity, and (most important) experimental verification.
Once you know your basic operations addition<span>, </span>subtraction,multiplication<span>, </span>division <span>you will encounter story problems also known as word problems that require you to read a problem and decide which operation to perform in order to get the answer. There are key words here that often indicate which operation you will use. We will give you a list of them, but remember that for many problem</span><span>s </span><span>there may not be a key word and you’ll have to use your best judgment in order to figure out what to do. </span>
Answer: 
hrs
<u>Step-by-step explanation:</u>
1st painter: 
2nd painter: 
1st + 2nd = Together
+ = 
+ 
= 
4x + x = 8
5x = 8
x = 
=
Answer:
70°
found by considering A-frame ladder as a triangle
Step-by-step explanation:
Given that,
angle form on either side of A-frame ladder with the ground = 125°(exterior)
As it is a A-frame ladder so its a triangle, we will find the angle at the top of ladder by using different properties of triangle
1) find interior angle form by A-frame ladder with the ground
125 + x = 180 sum of angles on a straight line
x = 180 - 125
x = 55°
2) find the angle on top of ladder
55 + 55 + y = 180 sum of angle of a triangle
110 + y = 180
y = 180 - 110
y = 70°
Each method works diffrently the angles inside them is what matters.
