Euclid was an ancient greek scholar who? a: wrote a geometry textbook that was used for nearly 2,000 years. b: calculated the value of the infinite number known as pi. c: computed the circumference of planet earth. d: developed military tactics that still apply today.

The correct Answer is A: wrote a geometry textbook that was used for nearly 2.000 years.

Euclides -maybe helped by his followers- wrote a very important book called “The Elements” where he fixed 5 axioms (basic and simple postulates) from which he deduced all the knowledge in mathematics of Classical Greece.

This book was a work that lasted without variations until the 19th century and the concepts explained by it are still being studied in schools and universities.

Such is the case that sciences such as biology, astronomy, statistics, as well as several branches of engineering have received great contributions deduced from the knowledge developed in this book.

An indirect contribution very important for science in general and mathematics in particular is the development of the deductive method and its varied applications.

It was not Euclid who measured the diameter of the Earth but Eratosthenes, whose work was made a few years after Euclid's.

Euclid showed that the area of ​​the circumference is directly proportional to the square of its diameter, that is to say that the quotient between the area and the diameter is a constant, which is called pi, but it did not calculate its value, since it is an irrational number whose figures are endless.

the correct answer is =   british soldiers attacked and killed five boston townspeople.

1.3x - 2 - (3.3x + 5) = 2x + 1

1.3x - 2 - 3.3x - 5 = 2x + 1

-2x - 7 = 2x + 1

-7 = 4x + 1

-8 = 4x

x = -2