(Physical Science) Potassium and nickel are in the same row of the periodic table. What do these elements have in common?

A. They have the same number of electron shells

B. They have similar reactivity

C. They have similar physical
properties

D. They have the same number of valence electrons​

Explain how fossils scientists make discoveries about the lives of organisms and about how environments have changed over time. plz hurry up it time

What is true of sea slugs in these orders

Astudent wants to test the hypothesis that fertilizer improves the growth rate of grass seeds. to test this hypothesis, the student put the same amount of grass seed in 3 containers with the same type of soil. the student measured the growth at the end of the week. all plants received equal amounts of water and sunlight. if you were asked to graph this data, what would you place on the x-axis? a. fertilizer b. water c. plant growth d. week one