The Oklahoma Pipeline Company projects the following pattern of inflows from an investment. The inflows are spread over time to reflect delayed benefits. Each year is independent of the others.

Year $1$ Year $5$ Year $10$

Cash Inflow Probability Cash Inflow Probability Cash Inflow Probability

$ $550\mathrm{.}40$ $ $400\mathrm{.}35$ $ $300\mathrm{.}30$

$800\mathrm{.}20800\mathrm{.}30800\mathrm{.}40$

$1050\mathrm{.}401200\mathrm{.}351300\mathrm{.}30$

The expected value for all three years is $$80.$ calculate standard deviation for years $1\mathrm{.}5\mathrm{.}10$