37. Predict the missing value (?) for radioactive francium (Fr). The atomic radius, density, and melting point are given for elements in Group IA/1. Element Atomic Radius 248 pm 266 pm

(?) pm Rb Cs Fr Density at 20 °C Melting Point 1.53 g/mL 39.3 °C 1.93 g/mL 28.4 °C (?) g/mL (?) °C