What kept most foreign invaders from China's lands? fearsome samurai
natural barriers such as seas, mountains, and deserts
soldiers placed along the Silk Road
Mongol warriors hired by China's emperors

offline recommendation systems option b

because recommendation systems produce a list of two ways

1. through collaborative filtering

or

2. through content-based filtering

is there answer chooses?

literally just took the test, got a 100%. i couldn't be bothered to type it all out, so i just took pictures.

should be in order from q 1 to 35.