Question

for select part, options are: (Increase, Decrease)

Пт, v where w is the win ch index, Tís he adual temperature, and y s the wind speed. A numerical is given in this In this example we considered the function l table. (a) What is the value of f-15, 70)? What is its meaning? f(f-15, 70) which means that if the temperature is -15°C and the wind speed is 70 km/h, then the air would feel equivalent to approximately oC without wind. (b) Describe in words the meaning of the question "For what value of v is n-20, v)--30?" The question is asking: when the temperature is oC, what wind speed gives a wind-chill index of OC7 PC? Answer the question. ˇ- km/h (c) Describe in words the meaning of the question "For what value of T is f(T, 20)43 km/h, what temperature gives a wind-chill index of The question is asking: when the wind speed is oC? Answer the question oC (d) What is the meaning of the function w -10, v)? Describe the behavior of this function The function W -10, v) means that we fix T at chill index values for different wind speeds when the temperature is and allow v to vary, resulting in a function of one variable. In other words, the function gives wind- eC. From the table (look at the row corresponding to T10), the function Select- and appears to approach a constant value as v increases (e) what is the meaning of the function W (T, 60)? Describe the behavior of this function. The function W f(T, 60) means that we fix v at index values for different temperatures when the wind speed is and allow T to vary, again giving a function of one variable. In other words, the function gives win d-chill km/h. From the table (look at the column corresponding to v 60), the function Select- almost linearly as T increases. EXAMPLE In regions with severe winter weather, the wind-chill index is often used to describe the apparent severity of the cold. This index W is a subjective termperature that depends on the actual temperature T and the wind speed o. So Wis a function of T and v, and we can write W-f(T, v). Table 1 records values of W compiled by the National Weather Service of the US and the Meteorological Service of Canada. TABLE 1 Wind-chill index as a function of air temperature and wind speed Wind speed (km/h) 510 15 2025 30 40 50 60 70 80 1 -2 23 579-11-121213-14 -15 16-16-17 1013 517 189 20 2122 23 2324 15-19 22324 252627 29 30-3031 20-24-27-293032 -33-3435-36-3738 2530-33-35-3738-394 42434445 -30-36394434446 48 4950-51-52 -354145-48-495152 -54-56-575860 -4047-5-5456-57-59 -66364-65-67 For instance, the table shows that if the temperature is -5°C and the wind speed is 50 km/h. then subjectively it would feel as cold as a temperature of about-15°C with no wind. So /(-5, 50) =-15

Answer 1

(a) f(45,10) = -30 which neans olttout coind -30c 30c temperature is &wind Chỉı'nda cb-зос , 20 Kob artable functian ohen the toreatue ts c, the function dececases oppars to approach a cohstant value as v increases C,60) it is decreasing hc tbe colnd speed is 60tr. The increases atrmost Uearly as incrces Cheut vo totom to top