1. Centimeter
2. Kilogram
3. Millisecond
4. DL
5. Kg
6. Mm
7. S
8. Mm
9. Us
<h2>
Answer: The half-life of beryllium-15 is 400 times greater than the half-life of beryllium-13.</h2>
Explanation:
The half-life 
of a radioactive isotope refers to its decay period, which is the average lifetime of an atom before it disintegrates.
In this case, we are given the half life of two elements:
beryllium-13: 
beryllium-15: 
As we can see, the half-life of beryllium-15 is greater than the half-life of beryllium-13, but how great?
We can find it out by the following expression:
Where 
is the amount we want to find:
Finally:
Therefore:
The half-life of beryllium-15 is <u>400 times greater than</u> the half-life of beryllium-13.
Answer:
1. all of them
2. cork and wax
3. iron, lead, and aluminum
4. none of them
Explanation:
1.Which material will displace a volume of water? all of them
When an object is introduced into a container with a volume of water, a volume of liquid equal to the volume of the object is displaced
2.Which material will displace a volume of water less than its own volume?
cork and wax
because the density of the object is less than that of the displaced liquid
3.Which material will displace a volume of water equal to its own volume?
iron, lead, and aluminum
because Arquimedes's principle: any body plunged inside a fluid in this case water experiences an ascending force called push, equivalent to the weight of the fluid removed by the body
4.Which material will displace a volume of water greater than its own volume?
None of them
multiply the six sides of the cube(LB), since length is 2000, then breadth will be 2000 also
