Determine the mean and variance of the random variable with the following probability mass function. f left-parenthesis x right-parenthesis equals left-parenthesis 8divided by 9right-parenthesis left-parenthesis 1 divided by 9right-parenthesis Superscript x Baseline comma x equals Number 0 , 1 , 2 , . . . Hint: Use the formula for the sum of the infinite series where .

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value

∠cbe and ∠deb are same-side interior angles.

i took the test

can you put the picture up?

step-by-step explanation:

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.