Timothy went to a baseball game. after the game, he wanted to ride the bus home. the red line and the blue line buses both stop at the stadium.
●the red line and the blue line bus left the stadium at 4: 00p. m.
●red line buses were scheduled to leave the stadium every 6mins.
●blue line buses were scheduled to leave the stadium every 8 mins.

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.

other answer is correct. i had used the radius of the radius somehow. a website: