Which of these pairs of elements have the same number of valence electrons?
hydrogen (h) and helium (he)
sodium (na) and potassium (k)
carbon (c) and oxygen (o)
boron (b) and beryllium (be)

The correct answer is the second option; sodium (Na) and potassium (K.)
Both sodium and potassium have the same number of valence electrons. 

Read the sentences below in 1962, i tried to enroll as the first black student at the university of mississippi. the governor of mississippi blocked my entrance which best describes the verbs used in the sentences? o they are past tense verbs, which are often used in narrative essays o they are past tense verbs, which are not often used in narrative essays. o they are future tense verbs, which are often used in narrative essays o they are future tense verbs, which are not often used in narrative essays.