If you can figure these questions correctly, I will make you brainliest!!!!

A salesman mixed two kinds of candies worth $1.25 and $1.6 a pound, respectively. He made a mixture of 70 pounds to sell at $1.4 a pound. How many pounds of each did he use?

A grocer has 18 kg of black tea worth $3.5 per kg. She wants to mix it with green tea worth $2.6 per kg to sell the mixture at $2.9 per kg. How much of green tea should she use?

How many quarts of a 50% solution of acid must be added to 20 quarts of a 20% solution of acid to obtain a mixture containing a 40% solution of acid

For the next RSM Award ceremony, it was decided to decrease the length of the main poster by 12% and to increase its width by 15%. By how many percent did the poster's area change? Did it increase or decrease

Just solve as many as you can, it will be appreciated!!!!