In the first quarter of$2017,$ a group of mutual funds had a mean return of $6\mathrm{.}4\%$ and a standard deviation of $2\mathrm{.}9\%.$ The returns were$$ well$-$described by a Normal model. According to the Normal model $$N$(6\mathrm{.}3\%,2\mathrm{.}2\%)$ determine what percentage of this group of funds you would expect to have the following returns.

a$.$ Over $6\mathrm{.}8\%?$

b$.$ Between $0\%$ and $7\mathrm{.}6\%$

c$.$ More than $1\%$

d$.$ Less than $0\%$