1 joule = 6,242e+18ev
20 joule = 20 joule *6,242e+18 ev/joule =1,248e+20 ev
1,248e+20 ev / (10 ev / photon) =1,248e+19 photons.
First,you do,2/5+2/3,but since you will need a common denominator,you will find the least common denominator for 5 and 3.The LCD(Least Common Denominator) will be 15 since both 5 and 3 could go in 15.Now,the equation looks like this: 2/15+2/15 since whatever you do to the bottom numbers,you NEED to do to the top numbers:2 and 2.Now you will need to do,2x3,since 5x3=15 and the answer to 2x3=6 then you do 2x5,since 3x5=15 the answer is 10 now the equation looks like this:6/15+10/15 now you add them together,and the answer will be 16/15 and if you want the answer to be a mixed number,it would look like this: 1 1/15. Hope this helps!
The answer is 148 degrees it’s congruent
Answer: The expressions for the length and width of the new patio are

And the area of the new patio is 384 sq. feet.
Step-by-step explanation: Given that Stephen has a square brick patio. He wants to reduce the width by 4 feet and increase the length by 4 feet.
The length of one side of the square patio is represented by x.
We are to write the expressions for the length and width of the new patio and then to find the area of the new patio if the original patio measures 20 feet by 20 feet.
Since Stephen wants to reduce width of the patio by 4 feet, so the width of the new patio will be

The length of the patio is increased by 4 feet, so the length of the new patio will be

Now, if the original patio measures 20 feet by 20 feet, then we must have

and

Therefore, the area of the new patio is given by

Thus, the expressions for the length and width of the new patio are

And the area of the new patio is 384 sq. feet.
I suppose you thought the following:
A) f(x) = 100^(x-5) - 1
B) f(x) = 3^(x-4) - 2
C) f(x) = 7^(x-1) + 1
D) f(x) = 8^(x+1) - 3
In that case the correct answers are A), B) and D)
Good luck!!!