The answer is A. Working the formula backwards you get that r^2=256, so r=16
Answer:
y=25600
y=100(2)^{2t}
y=252
Step-by-step explanation:
A bacteria culture starts with 100 bacteria and doubles in size every half hour.

where x represents the number of hours
(a) t= 4 hours
Plug in 4 for t and find out the number of bacteria y

25600 bacteria

convert 40 seconds into hour
40 divide by 60 =2/3

The graph is attached below
Answer:
the answer to 0.4 cubed is 0.064
N I believe but I’m not too sure