In this one problem I am given I=3.20A, L=4.2m, cross-section=.00220m, n=8.85*10^28, and e=1.6*10^-19. I am using an equation that is set up like this to find the t=((l*w)*n*q*L)/I When I calculate ((0.00220m)^2*(8.85*10^28)(1.6*10^-19)*(4.2))/(3.2) I get 8.99*10^4 and for some reason the sig. figs are wrong!! I don't know why????