For the following questions answer them individually
During the period between 1950 and 1990, the proportion of GDP contributed by agriculture significantly ____.
Which element of group 13 is a soft metal with a low melting point (303K) and is widely used in doping semiconductors and producing solid-state devices such as transistors?
What type of isomerism exists in compounds containing two or more complexes, each of which contains a different set of ligands that can in principle be replaced with a ligand of the other complex?