Convert the following for loop to a while loop to obtain the same result stored in the variable sum. $1$ double sum $=0\mathrm{.}0$; $2$ int threshold $=3$; $3$ for $($double j $0,$ k $=0$; j $<=$ threshold; j$+=0\mathrm{.}5,$ k$-=0\mathrm{.}5)4$ sum $+=$ XD$07$ j$*$j $+$ k$*$k;