The charge flowing in a conductor varies time as,
`q=at - 1/2 bt^(2) +1/6 ct^(3)`
Where a,b,c are positive constants. Then, find (i) the initial current (ii) the time after which the value of current reaches a maximum value (iii) the maximum or minimum value of current.
A. has an initial value `i=a`
B. reaches a minimum value after a time period `t=b//c`
C. reaches a maximum value after a time period `t=b//c`
D. has either a maximum or a minimum value `i=a-(b^(2))/(2c)`
