HELP Condense and evaluate the following expressions using identities:

1. cos pi/3 * cos (5pi)/6 - sin pi/3 * sin (5pi)/6

3. (tan 122 degrees - tan 32 degrees)/(1 + tan 122 degrees * tan 32 degrees)

4. 2sin 15 degrees * cos 15 degrees
You don’t have to answer all of them but it would be cool

How much dextrose 70% must be mixed with dextrose 5% to prepare 1,000 ml of dextrose 20%?

Ana drinks chocolate milk out of glasses that each holdof a liter. she has of a liter of chocolate milk in her refrigerator. 10 how many glasses of chocolate milk can she pour?

Someone answer asap for ! the boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a. e = 2b - 212 b. b = 2e - 212 c. e = -2b + 212 d. b = -2e + 212