Question 2. The life span of an insect is BLACK X (ladder unit) with a single night of XEU SU ( kx² ( 4 - x ) neu x = [ 0.4 ] f ( x ) = { kx² ( 4 0 if vice versa a / Find the mean and standard deviation of life expectancy X. b / Observe the life spans of those 20 insects and call Y the number of insects that die before it is 1 month old. What distribution , calculate EY , DY .

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 )