The answer is 30, can I get the brainliest answer
(a) (i) In first 4 minutes Mary's speed was 600 / 4 = 150 m / minute
(ii) in last 4 minutes her speed was (1000-600) / 4 = 400/4 = 100 m/min
(b) Marys average speed for the whole journey = 1000/8 = 125 m/min
(c) 200 m
(d) Peter arrived at school after 7 minutes . Mary took 8 minutes. Peter first.
(e) Where they met is given by where the 2 curves intersect. That is at time 6.8 minutes and 880 m from Mary's home
(f) At t= 4 dsitance between then is 600 - 400 = 200 m
Answer:
-2.
Step-by-step explanation:
f(0) = 0^2 + 8(0) - 2
= -2.
Answer:
- 3a³ + 5a² - 3a + 7
Step-by-step explanation:
Given
(a³ - 2a + 5) - (4a³ - 5a² + a - 2)
Distribute both parenthesis noting the second is distributed by - 1
= a³ - 2a + 5 - 4a³ + 5a² - a + 2 ← collect like terms
= (a³ - 4a³ ) + 5a² + (- 2a - a) + (5 + 2)
= - 3a³ + 5a² - 3a + 7
Using an exponential function, it is found that the Tequesta settlement is 1845 years old.
<h3>What is an exponential function?</h3>
The exponential equation for a decaying amount of a substance is given by:

In which:
- A(0) is the initial value.
- r is the decay rate, as a decimal.
Researching on the internet, the half-life of carbon 14 is of 5,730 years, hence A(5730) = 0.5A(0), which we use to find r.







Hence, the equation is:

The wood chips were found to contain 80% of the atmospheric carbon-14, hence we have to find t for which A(t) = 0.8A(0).







The Tequesta settlement is 1845 years old.
You can learn more about exponential functions at brainly.com/question/25537936