The smallest C-14 activity that can be measured is about 0.20%. If C-14 is used to date an object, the object must have died within how many years

13

step-by-step explanation:

distance formula is d=√(x2-x1)^2   +   (y2-y1)^2

0.02

step-by-step explanation:

time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 k (but other seconds are sometimes used in astronomy)

my guess would be b and d, but i didn’t actually get out the pen and paper. lol

its line 2 i just added the rest or else it wouldn't let me answer