Summarize four pregnancy-prevention methods. discuss the benefits, effectiveness, and risks of each.

Below are the summarized facts of Four Pregnancy-Prevention Methods and their benefits, effectiveness, and risks:

1.) Physical Barriers - Most common form of prevention. Using a male condom is the "most" effective of the physical barriers and decreases chances of getting an STD. 98% effectiveness. Risks of using physical barrier contraceptive is that non-condom barriers like female condoms and diaphragms can easily be moved during sexual intercourse and be considered useless.

2.) Abstinence - Almost 100% effective method. An STD-prevention method. The only risks of abstinence are, it does not 100% prevent pregnancies and STDs

3) IUDs - When placed in a woman's uterus, it'll prevent ovulation and it will be considered almost impossible for a pregnancy to occur. IUD's are 99.6% effective and only needs to be installed once and not be dealt with for many years usually. Does not prevent STDs and requires  professional doctor to have them placed inside.

4.) Pills - This method is considered 99% effective if pills are taken everyday and regularly but it is 91% effective when skipped or forgotten. An individual female can take a pill everyday to decrease her chances of becoming pregnant in means of changing body's hormonal levels. Pills do not require any physical barriers and doesn't need to be taken directly before or during intercourse. The risk is it does not prevent either partner from contracting an STD.

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step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

1 the 1st term, 3 the 2nd term, 6 the 3rd term,etc.

note the following:

from the 1st term (1) to the 2nd term (3), we go up by 2,from the 2nd term (3) to the 3rd term (6), we go up by 3from the 3rd term (6) to the 4th term (10), we go up by 4, andfrom the 4th term (10) to the 5th term (15), we go up by 5.

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

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