About how long does it take for the reaction to reach equilibrium in this concentration versus time graph? A. 0.5 second B . 1.5 seconds C. 2.5 seconds D. 4.5 seconds

How do i do this activity, is appreciated

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?

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?