Hello! How do I add a bio? I am new to btw! :)

The walls of valhalla were hung with shields; its ceiling glittered due to polished spearheads. read the passage. look at the underlined sections marked number (17). there may be a mistake in the way the sentence is written. if you find a mistake, choose the answer that corrects the mistake. if there is no mistake, choose ‘correct as is.’

Why did mao zedong begin the cultural revolution? select all that apply

These two elements threaten ecosystem biodiversity.