Could anyone Help ?? This is science.

Read the given expression. x = number of protons − number of core electrons which of the following explains the identity of x and its trends across a period? x is the effective nuclear charge, and it remains constant across a period. x is the screening constant, and it remains constant across a period. x is the effective nuclear charge, and it increases across a period. x is the screening constant, and it increases across a period.

How many moles of potassium hydroxide are needed to completely react with 2.94 moles of aluminum sulfate

How does climate change cause the ocean's thermohaline current to slow down?