If z is an even integer which of the following expressions must represent an odd integer?

There is no choice on your list that must represent an odd integer.

If  'z'  is an even integer, then (z-1) and (z+1) must both be odd integers.

Just divide the x axis (the top) by 2 or multiply the y axis (the bottom) by 2

Hello!

the answer is:

the correct option is the option b.

why?

to calculate the surface area of the right cylinder, we need to use the following formula:

from the picture we know that:

so, substituting and calculting we have:

hence, we have that the correct option is the option b.

have a nice day!