monotonically increases

monotonically decreases

increases to a maximum value and then decreases

decreases to a minimum value and then increases

$${e^{ - 2t}}\,u(t)$$

$${e^{2t}}\,u(t)$$

$${e^{ - t}}\,u(t)$$

$${e^t}\,u(t)$$

$$A(\omega ) = C{\omega ^2},\,\,\phi (\omega ) = K{\omega ^3}$$

$$A(\omega ) = C{\omega ^2},\,\,\phi (\omega ) = K\omega $$

$$A(\omega ) = C\omega ,\,\,\phi (\omega ) = K{\omega ^2}$$

$$A(\omega ) = C,\,\,\phi (\omega ) = K{\omega ^{ - 1}}$$

$$\delta (t) = \left\{ {\matrix{ {1,} & {t = 0} \cr {0,} & {otherwise} \cr } } \right.$$

$$\delta (t) = \left\{ {\matrix{ {\infty ,} & {t = 0} \cr {0,} & {otherwise} \cr } } \right.$$

$$\delta (t) = \left\{ {\matrix{ {1,} & {t = 0} \cr {0,} & {otherwise\,\,\,and\,\,\int\limits_{ - \infty }^\infty {\delta (t)\,dt = 1} } \cr } } \right.\,\,$$

$$\delta (t) = \left\{ {\matrix{ {\infty ,} & {t = 0} \cr {0,} & {otherwise\,\,\,and\,\,\int\limits_{ - \infty }^\infty {\delta (t)\,dt = 1} } \cr } } \right.\,\,$$