Given an arithmetic sequence with a5= 6 and a11= 48,

1.) What is the common difference of this sequence?
a. 5
b. 7
c. 9
d. 11

2.) What is the first term of this sequence?
a. -56
b. -34
c. -29
d. -22

3.) If we insert five arithmetic means between a5 and a11, what are those numbers?
a. 11,16,21,26,31
b. 13,20,27,34,41
c. 12,18,24,30,36
d. 15,20,25,30,35

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