Giveing brainilist to right answer

A. -10.21

Step-by-step explanation:

We know that he bought 3 sets of pencils for $30.63, so assuming each set costs the same amount, we divide 30.63 (the total cost) by 3 (the number of sets purchased) which would give us 10.21. Because we know that this money would have been subtracted from his bank account, then we know that it is a negative number.

Meaning the final answer would be -10.21

answer: i think it's a

step-by-step explanation:

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.