If X is a random variable with expected value 2, then the expected value of 5X will be:

E(5X) = 10

Step-by-step explanation:

The expected value of a random variable X is denoted as; E(X)

Now we are told it's equal to 2.

Thus;

E(X) = 2

Now, we want to find the expected value of 5X

We will use the principle from expected value derivations below;

E(cX + d) = cE(X) + d

Also;

If E(X) = z

Then;

E(aX) will give; aE(X) = az

From our question, we have;

E(X) = 2

Thus;

E(5X) = 5E(X) = 5 × 2 = 10

d. millimeters per hour.

step-by-step explanation:

we are given that,

carlo used a rain gauge to measure the amount of water his lawn is receiving from the sprinklers.

since, according to the options, we see that,

water cannot be measured by 'miles per hour', 'meters per second' and 'grams per seconds'.

we get that, the water can be measured by 'millimeters per hour'.

hence, the appropriate rate for describing the amount of water is 'millimeters per hour'.

answer: it's d

step-by-step explanation: