You are in an old spy movie, and have been locked into a small room (volume 1000 ft). You suddenly realize that a poison gas has just started entering the room through a ventilation duct. Recognizing the type of poison from its smell, you know that if the gas reaches a concentration of 100 mg/m, you will die instantly, but that you are safe as long as the concentration is less than 100 mg/m. If the ventilation air flow rate in the room is 100 ft/min and the incoming gas concentration is 200 mg/m, how long do you have to escape?

Which branches of natural science include the study of an organism that lived 10 million years ago

The movement of electrons between atoms is called an

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".