Answer: Hello mate!
you know that the equation is (or at least i think this is):
p(t) = 800 + 9t/90 + t^2
You want to know the "rate of change" after 6 hours.
We know that the rate of change is the derivative of P(t) with respect to t; this is

now we want the rate of change when t = 6, then we replace t by 6 in the derivate equation:

so the rate of change after 6 hours is 12.9
where 
If the equation is wrong ( because you write P(t) = 800 1 + 9t 90 + t2, and i don really know how to iterprete it) tellme and we can do the derivate again :D
If the decimal is 1 number divide that number into 10 Then simplify the fraction if possible. if the decimal are 2 numbers divide those 2 numbers by 100 Then simplify the fraction if possible
3 numbers:by 1000, etc
Ex 0.4= 4/10 = 2/5
Holly would have to climb 92 flights of stairs in the fifth week
Using it's concept, it is found that the probability of being a girl and choosing lemonade is given by:
b. 0.2.
<h3>What is a probability?</h3>
A probability is given by the <u>number of desired outcomes divided by the number of total outcomes</u>.
In this problem, out of 130 people, 26 are girls who choose lemonade, hence the probability is given by:
p = 26/130 = 0.2, which means that option b is correct.
More can be learned about probabilities at brainly.com/question/14398287
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