1) A jet took 6h to fly against headwinds of 50 miles/hour from city A to B. It took 5H on the return trip when the winds became tailwinds of 50miles/hour. How fast does the jet travel relative to the air? 2) The ammount of heat H which passes through wall "t" thick is proportional to the product of the area "A" of a wall T2 - T1, the differnce in temperature of the surfaces of the wall and is inversly proportional to "t". Express the equation and solve for T2. For #2 I got to: T2 = ((HT) / A) + T1 Is that right? thanks. Thanks alot guys, been havinga lot of trouble with these.