The amount of time a certain brand of light bulb lasts is normally distribued with a mean of 1500 hours and a standard deviation of 90 hours. Out of 165 freshly installed light bulbs in a new large building, how many would be expected to last more than 1640 hours, to the nearest whole number?

Idrk but i think u should figure out the n dia n then the units it will make it way more easier

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 )