Write down in terms of n, an expression for the nth term of the following sequences
a) 25 20 15 10 5

The nth term will be:

Step-by-step explanation:

Given the sequence

25, 20, 15, 10, 5

An Arithmetic sequence has a constant difference 'd' and is defined by

Computing the common difference of all the adjacent terms

As the difference between all the adjacent terms is the same and equal to

Also, the first term is:

Hence, the nth term will be:

       ∵ ,

Therefore, the nth term will be:

it costs $20 to interview each person for a survey. find the cost to obtain a +- 3% margin of error.

step-by-step explanation:

copy and paste, put it in google

c. 6tan80

step-by-step explanation: