The next term of the AP 
is
Here, first term = √7
Common difference = √28 - √7 = 2√7 - √7 = √7
Next term = T4 = T3 + d
= √63 + √7
= 3√7 + √7
= 4√7
= √112
3
The next term of the AP is
Here, first term = √7
Common difference = √28 - √7 = 2√7 - √7 = √7
Next term = T4 = T3 + d
= √63 + √7
= 3√7 + √7
= 4√7
= √112