Mantle of the earth crust is ?
Step 1: The Earth's structure is divided into crust, mantle, and core.
Step 2: The mantle lies below the crust and extends up to 2,900 km deep.
Step 3: It consists of semi-fluid silicate minerals, enabling tectonic plate movement (asthenosphere). \[ \boxed{\text{Semi-fluid mineral matter}} \]
Find the missing code:
L1#1O2~2, J2#2Q3~3, _______, F4#4U5~5, D5#5W6~6
Find the missing number in the table.