Relative maximum: the point on the graph where the interval changes from A. Increasing B. Decreasing C. Input D. Output

Two blends of tea are mixed to make a blend that will be sold at the fair. black tea sells for $2.20 per pound and orange pekoe tea sells for $3.00 per pound. how much of each should be used to obtain a 4lb blend selling for $2.50 per pound?

Me asap! what is the slope of this line? enter your answer in the box.

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.