A fair (unbiased) coin was tossed four times in succession and resulted in the following outcomes; (i) Head, (ii) Head, (III) Head, (iv) Head. The probability of obtaining a ''Tail'' when the coin is tossed again is

The annual precipitation data of a city is normally distributed with mean and standard deviation as $$1000$$mm and $$200$$ mm, respectively. The probability that the annual precipitation will be more than $$1200$$ mm is

Two coins are simultaneously tossed. The probability of two heads simultaneously appearing

Three values of $$x$$ and $$y$$ are to be fitted in a straight line in the form $$y=a+bx$$ by the method of least squares. Given $$\,\,\,\sum x = 6,\,\,\sum y = 21,\,\,\sum {{x^2} = 14,\,\,\sum {xy} = 46,\,\,\,\,} $$ the values of $$a$$ and $$b$$ are respectively