The ancient greeks were very interested in number patterns.

C) a(n) = ⁿ⁽ⁿ ⁺ ¹⁾/₂

Step-by-step explanation:

We can plug in, for example, 1 for n. And if n = 1, since it is the first number of the sequence, the new number should also be 1.

A) 2 * n --> 2 * 1 --> 2; 2 ≠ 1, so A is incorrect.

B) n²/2 --> 1²/2 --> 1/2; 1/2 ≠ 1, so B is also incorrect.

C) 1(1 + 1)/2 --> 2/2 --> 1; 1 = 1, so C could be correct.

D) (1  + 1)/2 --> 2/2 --> 1; 1 = 1, so D could be correct.

Since either C or D could be correct, we can plug in n = 2 to see if it will be 3.

C) 2(2 + 1)/2 --> 6/2 --> 3; 3 = 3, so C could be correct.

D) (2 + 1)/2 --> 3/2 --> 3/2 ≠ 3, so D is not correct.

From this, we can conclude that C is the correct answer.

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have

0.02

step-by-step explanation:

time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 k (but other seconds are sometimes used in astronomy)