What is the value of a2 in the sequence?2, 5, 10, 17, ...251017What is the value of a3 in the sequence?−4, −2, −1/2, −1/4, ...−4​ −3 ​​ −1/4​ −1/2 ​Which answer describes the type of sequence?3, 9, 15, 21, ...arithmeticneither arithmetic nor geometricgeometricWhich answer describes the type of sequence?4, 9, 13, 22, ...arithmeticneither arithmetic nor geometricgeometricWhich answer describes the type of sequence?200, 40, 8, 1.6, ...geometricneither arithmetic nor geometricarithmetic