The current, lo (measured in amperes). decreases to amperes after t seconds according to the formula I = loe^-0.511 When 8 amperes decreases to 3.2 amperes, the equation is 3.2 = 8e^-0.51t Rounded to the nearest tenth of a second, how long, t, does it take for the current to decrease from 8 amps to 3.2 amps?
t=0.4 second
t=1.8 seconds
T= 2.5 seconds
t=0.7 second

Amachine that produces a special type of transistor (a component of computers) has a 2% defective rate. the production is considered a random process where each transistor is independent of the others. (a) what is the probability that the 10th transistor produced is the first with a defect? (b) what is the probability that the machine produces no defective transistors in a batch of 100? (c) on average, how many transistors would you expect to be produced before the first with a defect? what is the standard deviation? (d) another machine that also produces transistors has a 5% defective rate where each transistor is produced independent of the others. on average how many transistors would you expect to be produced with this machine before the first with a defect? what is the standard deviation? (e) based on your answers to parts (c) and (d), how does increasing the probability of an event a↵ect the mean and standard deviation of the wait time until success?