beans cost 600$ for 1 killogram if i buy 9 grams of beans and my friend buys 70 grams of beans how much more did my friend pay

Aman steps out of a plane at a height of 4,000m above the ground falls 2,000m very quickly and then opens his parachute and slowly falls the remaining 2000m to the ground what height above the ground would be the best choice for a reference point

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4

What’s the answer ? use the picture to see the problem