Answer:
option (A) —Permutation.
Step-by-step explanation:
this is because permutation comes in this form and looks like that and I have learnt permutation in the past.
so yeah;
examples of permutations:
²⁰p9 ( 20 upper case, 9 lower case and p in-between)
we can solve it by
Formula: n!/(n-r)!
soooo
20!/(20-9)!
= 20!/(11)!
=20x19x18x17x16x15x14x13x12x11!/11!
we cancel out the 11!s (for easier solving)
and multiply or cancel out the remaining ( if you can't cancel out yet just multiply)
we get,
6.09493248 x 10¹⁰
~ 6 x 10¹⁰
there you go.( I know I did a little bit too much)
Hope this helps
Good luck.
