CPhill

The first is symmetric about the origin...so it is odd

The second is also symmetric about the origin...so....odd

The last is symmetric about the y axis....this is characteristic of an even function

2000 / 3   =   666 + 2/3  ≈  666.66667

P(2 girls)  = C(3,2) (1/2)^3  =  3 * (1/8)  =   3/8

D. P(A) * P(B) = P(A and B)

a₁  = 2

a_n  = (1/3)a_{n - 1}

The explicit rule is

a_n  = 2(1/3)^n-1

B is correct

If independent   P(A and B )  = P(A) * P(B)...so.....

(0.5) (0.2)  =  0.1

D. P(A) = 0.5, P(B) = 0.2, P(A and B) = 0.1

If independent 

P ( A and B)  =  P(A) * P(B)  = (0.5) (0.3)  = 0.15

ES.....I'm guessing that you want P( 1 red and 2 yellow)   (???)

If so...we have

We have

C(5, 1) * C(5, 2)              5  * 10                50                5

______________  =     _________  =    _____   =     ___

    C(10, 3)                         120                 120              12

1/2  of the natural numbers from 1 to 50  are even

So

P(even)  = 1/2   =  equally likely