Answer: First Option : Sₙ= n/2(a₁ + aₙ)
Step-by-step explanation:
The nth partial sum of an arithmetic sequence or the sum of the first n terms of the arithmetic series can be defined as the sum of a finite number of term in an arithmetic sequence.
It is calculated using the formula:
Sₙ= n/2(a₁ + aₙ)
Where :
a₁ = First term
aₙ = last term
n = number of terms
Answer:
Lines 3 and 4
Step-by-step explanation:
Let's examine the slope of each of the given lines to have the exact value and be able to answer the question. We use the definition of: 
Line 1: 
Line 2: 
Line 3: 
Line 4: 
Line 5: 
Therefore the lines that have slope strictly greater than 1 and less than 2 are:
Lines 3 and 4
To find the measurement of PS, you would add the lengths of PQ and PS. 18.4+4.7=23.1. The answer is 23.1 cm
Answer:
0,55
Step-by-step explanation: