Answer:
B
Step-by-step explanation:
its pretty simple just try that answer
42 times 28 is how you will get the area. If you need perimeter then just do (42 times 2) plus (28 times 2) and there you go:)
Combinations
nCr
you have n items and how many ways are there to chose r of them
nCr=

remember than n! means n times all numbers before like
3!=3*2*1, 5!=5*4*3*2*1
9 stations, how many ways are there to chose 6 of them
9C6=

=

=

=

=

=
84
84 ways