For the Data $(0,400),(1,350),(2,300),(3,220),(4,200),(5,180)$ , Where the First Number in Parenthesis Is

Multiple Choice

For the data $(0,400) ,(1,350) ,(2,300) ,(3,220) ,(4,200) ,(5,180)$ , where the first number in parenthesis is $t$ and the second number is the actual demand, if we fit a trend line of the form $y t=a+b t$ , the value of $a$

A) must be 400
B) must be between 180 and 400
C) can be calculated using the formulae
D) will not be exactly equal to 400
E) C and D