Hm Every hour, a research assistant removes half the mass of a bacteria culture originally Wayne 4800 µg to observe under a microscope. The research assistant will stop this process once the mass is equal to 300 µg.

-12 > a

step-by-step explanation:

-11 > 1 + a

subtract 1 from each side

-11 -1> 1 -1+ a

-12 > a

i think the answer is b

to find the perimeter, you add up all the lengths of the sides. in this case you would have to add up 18+22+40+80 which equals 160.