Answer:
The second and the third one
Step-by-step explanation:
2,213,000, 6 is closer to 10 than 0.
This will be 2400 cause there is nothing in the ones place
Answer:
60.5 milligrams per square centimeter First, determine how many half lives have expired by dividing the time by the half-life. So: 55/20 = 2.75 That means that only 2^(-2.75) = 0.148650889 = 14.8650889% of the original substance remains. So just divide the amount remaining by 0.148650889 to get the original amount. 9 / 0.148650889 = 60.5445419 So originally, there was 60.5 milligrams per square centimeter 55 years ago.
Answer:
$24.50
Step-by-step explanation:
60% of $50= $30
$50-$30= $20
15% of $20= $4.50
$20+$4.50= $24.50