A sidewalk is to be constructed around a swimming pool that measures (b= +_ 0.1) m by (l= +_ 0.1) m. If the sidewalk is to measure (1.00 +_ 0.01) m wide by (t= +_ 0.1) cm thick, what volume of concrete is needed and what is the approximate uncertainty of this volume where ? li= bi=
dl= dli=