The answer is C Mario’s walking rate is 9 mph
The half-life of Po is 139 days, so its decay rate is
0.5 = e^(139k) ==> k = ln(0.5)/139
After some time t, 80% of the material will have decayed and you'll be left with a sample 20% of its original mass:
0.2 = e^(kt) ==> t = ln(0.2)/k = ln(0.2)/ln(0.5) * 139 = 322.748
so your sample is usable for about 323 days.
Answer:
You need to link a diagram
Step-by-step explanation:
Try taking a screenshot or picture and attach it to the question so we can actually see the diagram
Answer:
Divide 9 from both sides
Step-by-step explanation:
9x = 45
