The shadow of a tower on level ground is $30\ \text{m}$ longer when the sun's altitude is $30^\circ$ than when it is $60^\circ$. Find the height of the tower. (Use $\sqrt{3}=1.732$.)
Match sequencing methods with key feature. 
Match the technique with its application. 
Match the RNA type with its function. 
Match the enzyme with its function. 
Match the hypersensitivity type with its example. 