Answer:
Step-by-step explanation:
B looks good
I believe the answer is 6.28
Answer: The answer is 23x/63+1/4
1.Write equation
2.Factor completely
3.Apply a zero product rate
4.solve linear equations in step 3
Answer:
a) Two half lives, b) 
Step-by-step explanation:
a) The polonium-210 has a half life of 138.4 days. Therefore, 1.994 half lives have past.
b) Mass decay is described by the following exponential model:

The time constant for the isotope is:


The mass of the isotope after 276 days is:

