Which element has six energy levels?

a) rubidium (rb)

b) cesium (cs)

c) potassium (k)

d) sodium (na)

Why do scientists look for patterns in the world? a. patterns can explain observations. b. patterns never change, no matter what. c. patterns are easy for scientists to detect. d. patterns are all the same, through all time.

The chemical equation below shows the reaction of sodium (na) and chlorine (cl) to form sodium chloride (nacl). 2na + cl2 → 2nacl in this equation, which of the following is a reactant? i. sodium ii. chlorine iii. sodium chloride

Read "who built the pyramids? ”. leave this link open while you answer the questions throughout the assignment. give at least two reasons why some people claim the pyramids of giza were constructed by aliens.