For real $$x,$$ the maximum value of $${{{e^{Sin\,x}}} \over {{e^{Cos\,x}}}}\,\,$$ is

Assume that the duration in minutes of a telephone conversation follows the exponential distribution $$\,f\left( x \right) = {1 \over 5}{e^{ - x/5}},\,x \ge 0.\,\,\,$$ The probability that the conversation will exceed five minutes is

For the function $${{\sin z} \over {{z^3}}}$$ of a complex variable z, the point z = 0 is

The polynomial $$\,p\left( x \right) = {x^5} + x + 2\,\,$$ has