Perform the following operations :
`2.112 xx 10^6 - 3.5 xx 10^5`

Perform the following operations : 4.11 xx 10^-3 + 8.1 xx 10^-4

Perform the following operations : 4.11 xx 10^(-3)+ 8.1 xx 10^(-4),

Perform the following operations : 1.05 xx 10^-4 -9.7 xx 10^-5

Perform the following operations : 3.971 xx 10^7+ 1.98 xx 10^4

Perform the following operations : 3.97 xx 10^7 + 1.98 xx 10^4

Write each of the following in exponential notation : 0.00477 xx 10^5

Write each of the following numbers in ordinary decimal form : 3.75 xx 10^-5

Write each of the following numbers in ordinary decimal form : 5.16 xx 10^-3

Write down the number of significant figures in the following: 0.003 m^2 , 0.1250 gm cm^(-2), 6.4 xx 10^6 m, 1.6 xx 10^(-19)C, 9.1 xx 10^(-31)kg .