Misc: What's the smallest known planet in our solar system?

Questions

Which italian scientist is said to have dropped cannon balls from a tower to study how they fell to earth?

Caliph Harun al-Rashid of Baghdad featured in which series of eastern stories?

What is the most famous church designed by Sir Christopher Wren?

Who captured Constantinople in 1453?

What kind of engine did the greek engineer Hero design in the 1st century?