First you want to square the numbers, for example 101 squared is 10201 then you square 99 which is 9801. Squaring a number is multiplying it by its self so what you’re actually doing is 101*101, same with 99. Then you subtract the two numbers you just got so 10201-9801= 400 so the first answer is 400
The same goes for the second one so
1.03*1.03= 1.0609 then 0.97*0.97= 0.9409, then once again subtract to get your answer
1.0609-0.9409= .12 so 0.12 would be you’re answer :)