Angle sum theory

A)70°

B)65°

C)53°

D)60°

The longer leg of a 30° 60° 90° triangle is 16 times square root of three how long is a shorter leg

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?

Find the area of the regular hexagon if a side is 20 cm.