Help, I don’t know this problem

So, the answer is 13.

Step-by-step explanation:

(8r + 5) + (5r + 6) = 180  First collect the like terms

8r + 5r + 5 + 6 = 180

13r + 11 = 180

13r = 180 - 11

13r = 169  Now, divide both side by 13

r = 13

Let's check!

(8r + 5) + (5r + 6) = 180   Now, put 13 on the variables which is "r".

(8(13) + 5) + (5(13) + 6) = 180

(104 + 5) + (65 + 6) = 180

109 + 71 = 180

180 = 180

the answer would be 150 books

step-by-step explanation:

if you divide 300 by 2 you will get 150

the answer is: d) o, f, and kr.

atomic radius of bromine (br) is 114 pm.

atomic radius of oxygen (o) is 73 pm.

atomic radius of fluorine (f) is 72 pm.

atomic radius of krypron (kr) is 112 pm.

the atomic radius of a chemical element is a measure of the size of its atom.

the atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.

the atomic radius decreases across the periods because an increasing number of protons, because greater attraction between the protons and electrons.