If the volume is increased the number of collisions per second will decrease or increase

Answer

Decrease

Explanation:

As surface area will also increase the particles are less likely to collide on a regular basis.

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current