A tall stack of books is sitting on a table. One of the reasons the book stay where they are is because- Choices:

A: The chair is helping to hold the table up.

B: The table is exerting a balanced force on the books.

C: The books are exerting an unbalanced force on the table.

D: The books keep shifting enough to keep the stack balanced.

Please help me!

The lattice enthalpy (formation of ionic solid from ions in the gas phase) for agcl(s) is -916 kj/mol and the hydration enthalpy (dissolution of gaseous ions into water) is -850 kj/mol. how much heat (in joules) is involved in forming 1l of saturated agcl solution (1.8 × 10-4 g / 100 ml water) by dissolving agcl(s)? assume solution volume does not change much upon dissolution. the equations are given below. ag+(g) + cl−(g) æ agcl(s)