Name three elements that are likely to react in a similar way to: a sodium b fluorine

sodium - The ones "most" similar would be the ones closest in mass as well. Those would be Lithium (Li) and Potassium (K). Of those, I would consider Lithium to be "closest" as it shares the higher reactivity with sodium compared to the heavier elements in the Group.

fluorine - oxygen , chlorine and uranium are the most known elements that are likely to react in a similar way.

Explanation:

hope it helps

can you attach a picture of the lettuce? : )

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.