Answer:
READ THIS FIRST!!!
I am not going to right the parragraph (it says to use your own words, they could trace it back to me if you use my words, and you would get it trouble).
But I will tell you the forces acting on the pencil:
Gravity (pulls on the pencil)
Your hand (pushing it up canceling out gravity)
And the electromagnetic force (holding the thing together)
Hope it helped,
Have a good day
Lead-207 can change into Lead-208.
When Lead-207 is bombarded with neutrons, the atom acquires the neutron. Adding a neutron only changes the mass number of the atom. This does not involve change in the identity of the atom. So, Lead-207 can change into Lead-208 without change in its chemical properties.
It’s b because a spring of negligible mass then if u multiply
1) A The 78g
2) C Push on the wagon in the opposite direction as Jack with a force that is the same as Jack is applying.