Which of the following is a chemical weathering agent? 1.) acid produced by plants growing on rocks

2.) growing tree roots

3.) burrowing animals

4.) ice wedging

PLEASE HELP ME FAST ASAP

As we move from left to right across the periodic table, what is the general trend? a) atomic radii increase. b) electronegavitiy decreases. c) nuclear shielding increases. d) metallic character decreases.