$1.$ Give a brief description of how to compute the additive, XOR$-$based, and Fletcher checksums. Check that your description is accurate by using the checksum.py simulator$\mathrm{.}2.$ Is it possible to pass a $4-$byte data value $($using the $-$D flag$),$ that does not contain any zeroes, and leads to the additive and XOR$-$based checksum having the same value? If so$,$ under what conditions does this occur?$3.$ Use the simulator to compute checksums twice $($once each for a different set of numbers. The sets should not share any common numbers$).$ Find two sets of numbers that produce the same additive checksum. Give a brief description of when the additive checksum will be the same, even though the data values are different$\mathrm{.}4.$ Repeat Exercise $3$ for the XOR checksum$\mathrm{.}5.$ Compute the different checksums for the data set $-$D $1,2,3,4.$ Compare computing these checksums against $-$D $4,3,2,1.$ Give a brief description of what you observe. How is Fletcher generally "better" than the additive checksum?$6.$ Find a set of data values that all yield the same Fletcher checksum. In general, when does this occur?