Oliver draws a line on his paper and from a point on the line draws a circle. he then measures the radius of his circle and constructs an arc inside his circle from a point on the circle. what is he trying to construct?
a) a square inscribed in a circle
b) a trapezoid inscribe in a circle
c) a pentagon inscribed in a circle
d) an equilateral triangle inscribed in a circle

You were told that the amount of time lapsed between consecutive trades on the new york stock exchange followed a normal distribution with a mean of 15 seconds. you were also told that the probability that the time lapsed between two consecutive trades to fall between 16 to 17 seconds was 13%. the probability that the time lapsed between two consecutive trades would fall below 13 seconds was 7%. what is the probability that the time lapsed between two consecutive trades will be between 14 and 15 seconds?