Can some with this second question

Express the following number in scientific notation. 0.026890 =

As you watch a surfer ride a wave towards the shoreline, what is the shoreline? a) displacement reference b) reference point c) coordinate plane d) cartesian boundary

The table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.