1) according to bohr's model of the atom, in which orbitals do electrons have the most energy?

a. innermost orbitals
b. outermost orbitals
c. middle orbitals

2) where are valence electrons located?

a. closest to the nucleus
b. in the outermost electron shell
c. inside the nucleus
d. in both the inner and outer electron shells

The answer is:

1) Outermost orbitals have the most energy.

The explanation:

In Bohr model we can see that the highest energy level is found in the outermost orbital , when the first orbital form and make a shell around the nucleus and its principal quantum number which has the symbol (n) is = 1

So the other orbital away from the nucleus is gradually assigned values:

n = 2  

n= 3

n=4

etc

and  the most stable and the lowest energy level is found in the innermost orbit.  

2) valence electrons located in the outermost electrons shell.

The explanation:

when:  

The number of electrons in the outermost shell of an atom gets its reactivity or tendency from it to form and make the chemical bonds with the other atoms.

This outermost shell is called the valence shell, and the electrons found in this shell are called valence electrons.

the volume increases