The atoms of some elements can be made radioactive by

1)placing them in a magnetic field
2)bombarding them with high-energy
particles
3)separating them into their isotopes
4)heating them to a high temperature

I think 4 I got it right on edg but i duno if its the same

Explanation:

what is the general relationship between a galaxy's distance from earth and its speed?

the answer is:

the farther away a galaxy is from us, the faster it is moving away from us.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.