Which of the following is true? A. The tenth term of the sequence 4, 7, 10, 13, ... is 30.
B
an = 11 + 6n and an =
11, if n = 1
an-1 + 6n, if n > 1
both define the same sequence.
C.
The sum of the first 12 terms of the arithmetic series with a = -5 and a 12 =
23
2
is 39.
O
D
2-1 (3i – 15)
= 450

Could someone with number 1 and 2

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.

What is the total area of the figure?