What is the answer for number one and possibly number two

1. 24

Step-by-step explanation:

There are 4 cities to choose from.  After visiting the 1st city, there are only 3 cities to choose from, etc (see below).

1st city  and   2nd city   and     3rd city   and   4th city

   4        x          3            x             2           x         1        =   24

2. 30,240

Step-by-step explanation:

There are 10 digits to choose from.  After choosing the first digit, there are only 9 digits to choose from (because you can't have duplicate digits in the combination) (see below).

1st digit  and  2nd digit  and  3rd digit  and  4th digit  and  5th digit

   10        x           9           x         8           x          7           x          6       = 30,240

answer: standard form is ax^2 + bx + c = 0

step-by-step explanation:

standard form is ax^2 + bx + c = 0

(2x + 1)(x - 2) = 0

distribute to get into standard form

2x^2 - 4x + x - 2 = 0

2x^2 - 3x - 2 = 0

a = 2, b= -3, c = -2

a is your answer

answer: the correct one is a

step-by-step explanation: