What is the probability that the fifth email he receied

It has been reported that 80% of all emails received is junk mail. Each morning a computer user turns on his computer and activates his email system.

a) What is the probability that the fifth email he receied will be the second piece of spam?

b) What is the mean number of emails until the second piece of spam arrives?

Why is it an important concept that atoms generally appear : why is it an important concept that atoms generally appear in whole number molar ratios to each other in chemical

A test consists of 10 true or false questions to pass the : a test consists of 10 true or false questions. to pass the test a student must answer at least eight questions

Determine how long it takes before its velocity is reduced : a cannon ball having a weight of 20lb is fired upward in the vertical direction with a muzzle velocity of 1200 fts.

How does the experimental empirical formula of hydrated : how does the experimental empirical formula of hydrated alum compare to the actual empirical formula? make sure to list

What is the probability that the fifth email he receied : it has been reported that 80 of all emails received is junk mail. each morning a computer user turns on his computer

Determine the velocity at the nozzle exit and the thrust : a pure jet engine operates on an ideal cycle. the pressure ratio is 13 and the turbine inlet temperature 830 k.

What is the probability that the fifth email received will : it has been reported that 80 of all email received is junk mail. each morning a computer user turns on his computer and

Find the net work per unit mass of cycle air the thermal : in a stationary gas turbine engine ambient air at 100 kpa and 300 degrees k enters the adiabatic compressor. after

What is the rate constant of a first-order reaction that : half-life equation for first-order reactions t120.693k where t12 is the half-life in seconds and k is the rate