Due to ever-changing technology, a new xyz smartphone decreases in value 20% each year. (a) how much will this $1000 phone be worth in 2 years? (b) how long until it is worth less than 10% of it's original price?

1.) $640 2.) 7 years.

Step-by-step explanation:

1000 x .2 = 200      1 yr

1000 - 200 = 800

800 x .2 = 160         2 yrs

800 - 160 = 640

640 x .2 = 128         3 yrs

640 - 128 = 512

ANYWAYS THIS WOULD TAKE TO LONG! SO HERE IS THE ANSWER TO B.

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

i believe the answer is c.