me thank yu need tu lern bout thangs like (...) & [...]
mi ges be...step1...[(6.4*10^-21) /10^-19] +5.9*10^-20 + 10^-21
become [10^+19/ (0.15625*10^+21)]+0.1694915254237288*10^-20 + 10^-21
term11=(10^19/0.15625*10^+21)=(1/0.15625)*10^(19-21)...=6.4*10^-2...=0.064
term12=0.16949152...*10^-20=0
term13=10^-21...=0
step 2...sqrt(0.064)=0.25298221281347
abs not needed