Answer:

a  

1

​  

=a=4

a  

2

​  

=9

Common difference=d=a  

2

​  

−a  

1

​  

=9−4=5

a  

30

​  

=a+29d=4+29×5=4+145=149

a  

10

​  

=a+10d=4+10×5=4+50=54

a  

30

​  

−a  

10

​  

=149−54=95‬