The formula d = t² + 5 t expresses a car's distance (in feet) from a stop sign, d, in terms of the number of seconds t since it started moving.
Determine the car's average speed over the interval of time from t = 4 seconds to t = 7 seconds.

The car's average speed is 16 feet per second.

Explanation:

The expression for the average speed is as follows;

Given expression of distance:

Put t= 4 s.

d(4)= 36 ft

Put t= 7 s in the given expression.

d(7)= 84 ft

Calculate the car's average speed over the interval of time from t = 4 seconds to t = 7 seconds.

A.S= 16 feet per second

Therefore, the car's average speed is 16 feet per second.

emily ruth's annual premium is $1058.50

step-by-step explanation:

emily ruth is a female of 27 years age purchasing 20 year endowment insurance with face value $25000.

from the given table,

for females, the age of a male 3 years younger should be used.

so, we have to check for 24 year male for 20 year endowment.

it is 42.34 for every $1000 face value.

for a face value of $25000,

it is 25 * 42.34 = $1058.50

∴ emily ruth's annual premium is $1058.50

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