Explain how the gcf is used to factor an expression?

When factoring, it's easier to "pick out" the GCF first because it makes it simpler to factor even further. Otherwise, you will be troubled with lots of numbers and variables, so it will just get confusing.

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.

the answer is option a you would get more money.it would be $250.

step-by-step explanation:

for option b 200/2=100=50% 100/2=50=25% 50/5=10=5% it would be $220