What is the number of electrons in the highest occupied energy level of an element in group 5a?
a. 5
b. 3
c. 8
d. 18

Which of the following is a testable hypothesis? a. if i brush my teeth, i will get fewer cavities than if i don't brush my teeth. b. green toothpaste tastes better than blue toothpaste or red toothpaste. c. smart, careful, healthy people always brush their teeth. d. it's wrong to not brush your teeth before you have an important conversation with someone.

Which part of earth’s surface receives the most direct rays from the sun? a) equator b) ocean c) poles d) mountains

Analyze the reaction to determine whether the reaction is exothermic or endothermic. explain your reasoning.