9. in principle, the sieve of eratosthenes settles the question as to whether a given positive integer is a prime, but it is impractical because of the immense amount of time and space it can take to carry out the process, even for computers. a better primality test consists of going through the factorisation process - if we have an integer n > 0 such that no prime less or equal to vn divides it, then the integer is prime. use this method to determine whether the given integer n> 0 is prime. show all necessary work. a) n 12,817 b) n 14,653

Answer: d. 39 cmin the diagram, the approximate length of the minor arc de is 39 centimetres.step-by-step explanation: the formula for the length of an arc in a circle is as displayed below.let the length of the minor arc de = xx = 2( pi )r × angle of sector / 360°from this, we will substitute the values given from the problem into the formula to obtain the length of the minor arc de.x = 2( pi )r × angle of sector / 360°r = radius = 25cmpi as an approximate value = 3.14angle of sector = 120°x = 2( 3.14 )( 25 ) × 120° / 360°x = 157 × 1 / 4x = 39.25x = 39 ( rounded to the nearest whole number as an approximate value )