Please answer question #12 and 13. Thanks moist. 12. A cubic meter of air holds
ID: 289276 • Letter: P
Question
Please answer question #12 and 13. Thanks
moist. 12. A cubic meter of air holds 12 grams of water vapor at 25 degrees Centigrade However, at 25 degrees, a cubic meter of air can hold a maáximum of 20 grams of water vapor. The relative humidity of this particular cubic meter of air is a) 12 %, b) 20 %, c) 408, d) 608, e) 808, f) 32 %. 13. An air mass has a current temperature of 12 degrees Centigrade, and is saturated. Due to prevailing winds, it is forced to rise to cross the Becker Mountains. Assume a wet adiabatic rate of 5 degrees per kilometer (1000 meters) and a dry adiabatic rate of 10 degrees per kilometer. If this air mass is forced to rise from its starting elevation of one kilo- meter to an altitude of 4 kilometers to cross the Becker Mountains, and then descends to an altitude of 1 kilometer on the downwind side of the mountain range, what will the temperature of the air be, once it returns to its starting elevation? a) 7 degrees, b)17 degrees, c) 27 degrees, d) 12 degrees, e) 22 degrees, f) 32 degrees. 14. If air temperatures drop and the amount of water vapor stays the same, the relative humidity will: a) remain constant, b) go up, c) drop, d) indeterminate from information given. 15. Which of the following is the most important of the four natural vegetation controls? a) soil type, b) slope factors, c) other nd animals, d) climate.Explanation / Answer
relative humidity = present water vapor in the air/ maximum vapor it can hold *100
question 12
RH = 12/20 *100 =60% option D will be the answer
question 13
first we have temperature of 12 degree and the air is saturated at 1 km altitude . now we have to move air 3 kms more to reach 4kms altitude. here we have given the gradient 5degree per kms decrease in temprature so for reaching 3 kms up we will have the temprature of air is -3 degree celcius. now again we have to decrease the altitude of air and the dry air gradient is 10degree per kms so for reaching again 1 kms altitude we have to decrease 3kms altitude so we have now temperature increase of 30degree and -3degree we have at 4 kms altitude so there we have temperature of 27 degree. so option C will be the right answer.