Please help i have no idea what calculator notation is and i already got 3 wrong

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?

Which expression will have the same sum as 3_8 + 1/4?

You buy five cds at a sale for $5.95 each. write an expression for the total cost of the cds.then use the distributive property and mental math to evaluate the expression.