What is z equal too ? me ! 10 points asap !

Awater tank holds 18000 gallons. how long will it take for the water level to reach 6000 gallons if the water is used at anaverage rate of 450 gallons per day

Prove that 16^4-2^13-4^5 is divisible by 11.

Select the correct answer what is the 10th term of the geometric sequence 3,6, 12, 24,48 a. 512 b. 3,072 c. 768 d. 1,536