Picture sliding a block down a smooth ramp. how would friction affect this block as it slid?

Can someone me with 3 and 4 plz. this is for masteries test.

The human activities in two locations are described below: location a: rampant use of plastic containers location b: excessive use of pesticides and fertilizers which statement is most likely true? location a will have poor air quality because plastic is biodegradable. location a will experience water scarcity because plastic absorbs moisture. the population of honeybees will increase in location b because production of crops will increase. the population of fish in location b will decrease because the water is contaminated.

What is the chemical formula for dihydrogen monoxide