Ayeast culture weighing 2 grams is removed from a refrigerator unit and is expected to grow at the rate of upper w prime (t )equals0.4 e superscript 0.4 t grams per hour at a higher controlled temperature. how much will the weight of the culture increase during the first 9 hours ofâ growth? how much will the weight of the culture increase from the end of the 9th hour to the end of the 18th hour ofâ growth?