To receive 3 log removal of Cryptosporidium, 7200 mg/L∙min of the CT level must be applied if chlorination is used as a definition. A plant operator initially applied 50 mg/L of free chlorine and maintained a contact time of 50 min. Then, he was ordered to increase the dose to 1500 mg/L, how much of the additional contact time is needed to reach the log removal goal?

If you were designing a bumper for a car, would you prefer it to exhibit elastic or plastic deformation? why? consider the functions of a bumper in both a minor "fender-bender" and a major collision.

Ariver flows from north to south at 8 km/h. a boat is to cross this river from west to east at a speed of 20 km/h (speed of the boat with respect to the earth/ground). at what angle (in degrees) must the boat be pointed upstream such that it will proceed directly across the river (hint: find the speed of the boat with respect to water/river)? a 288 b. 21.8 c. 326 d. 30.2

Prove the equivalence between the two statements of the 2nd law of thermodynamics (i.e., a violation of one statement leads to the violatio the other statement)