{f=((130*(k-340)/3300+1000)/1000)*(1+((200*(l-380)/3300+50)/1000)*((200*(l-380)/3300+400)/1000))*(1+0.25*(550*(m-380)/3300/1000))*(1/(1-130*(n-380)/3300/1000)),k=1242,l=2036,m=1931,n=3577}