Find the missing term in the following alphanumeric series: HN22, PT36, XZ50, ?, NL26

Refer to the following letter series and answer the question that follows. Counting to be done from left to right. (Left) S I C X Z O A K L N T E W A Q D F H G U K O (Right) How many such consonants are there, each of which is immediately preceded by a vowel and also immediately followed by a vowel?

Refer to the following letter and symbol series and answer the question. (Counting is to be done from left to right only): (Left) J W @ M E V ~ & P T ¥ G R Y € ! K C ◇ A D £ % B F $ I S L < Q % X Z (Right) How many such symbols are there each of which is immediately preceded by a letter and also immediately followed by another symbol?