How many 5 digit numbers have the property that all their digits are ascending.

So, for the ascending order, there are only 9 digits to choose from, and hence, there are 9C5 ways to choose the 5 digits. So, there can be 9C5=126 5-digit no.s with their digits in an ascending order.

126 5

v = 1/3 a^2h

step-by-step explanation:

the volume is 1/3 a^2h.

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.