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2 years ago

A sample pf a radioactive isotope had an initial mass of 370 mg in the year 2007 and

Mathematics

1 answer:

arlik [135]2 years ago

8 0

Answer:

I need help with this! PLEASE!!! SOMEONE HELP ME!

1.A space shuttle's wings are useless as it travels around the exosphere. Explain, in your own words, why the wings are so useless and how the shuttles can move around.

2.Explain, in your own words, the thermosphere and the stratosphere are our hottest atmosphere layers.

3.Explain, in your own words, how and why “shooting stars” occur. For example, why and what causes meteors to burn up.

4.Explain, in your own words, the importance of our ozone layer in the stratosphere.

5.Explain, in your own words, why weather only occurs in the troposphere.

please use your own words!

Step-by-step explanation:

You might be interested in

The heights of women aged 20 to 29 follow approximately the N(64, 2.72) distribution. Men the same age have heights distributed

Softa [21]

The z-score for men at 64 inches is:
$z=\frac{64-69.3}{2.84}=-1.866$
Using a standard normal distribution table, we can see that the cumulative probability for a z-score of -1.866 is 0.031.
The answer is 3.1%.

4 0

4 years ago

Given: PSTQ is a trapezoid. ST=4, PQ=25, PS=13, TQ=20 Find: Area of PSTQ.

babunello [35]

Answer:

174 units²

Step-by-step explanation:

There are a few different ways you can find the altitude of the trapezoid. Consider the attached figure with some points and lines added. SQ' is parallel to TQ, so Q'Q = 4 and PQ' = 21. Based on the side length of PS = 13, you can guess that the height is 12. (5-12-13 is a commonly-used Pythagorean triple.) This would make PP' = 5, P'Q' = 16, and triangle SP'Q' have side lengths 12, 16, and 20, corresponding to a 3-4-5 right triangle multiplied by 4.

Another way to find the height is to use Heron's formula for the area of triangle PSQ'. The side lengths are 13, 20, 21, so the half-perimeter is 27 and the area is √(27(27-13)(27-20)(27-21)) = √(9²·14²) = 126. The base of the triangle, PQ', is 21, so the height is ...

... h = 2A/b = 2·126/21 = 12

The area of parallelogram Q'STQ is then ...

... A = bh = 4·12 = 48

and the total area is the triangle area plus the parallelogram area:

trapezoid area = 126 + 48 = 174 . . . . units²

_____

Of course, with the height known, the usual formula for the area of a trapezoid can be used:

A = (1/2)(b1 +b2)h

A = (1/2)(25 +4)·12 = 29·6 = 174 . . . . units²

6 0

3 years ago

Which one represents a linear function help ong please !!

WINSTONCH [101]

Answer:

D is the correct answer

8 0

3 years ago

Use 3.14 for PI( π ) Diameter: 5 ft Formula: A= πr2

Liula [17]

Answer:

$\boxed {\boxed {\sf 19.625 \ ft^2}}$

Step-by-step explanation:

The area of a circle is found using this formula:

$a= \pi r^2$

We know the circle's diameter is 5 feet, but we don't know the radius. Remember the diameter passes through the center from one side to the other, while the radius connects the center and the side. Therefore, the radius is half the diameter.

r=d/2
r= 5 ft/2
r= 2.5 ft

We know the radius is 2.5 feet and we are using 3.14 for pi. Substitute the values into the formula.

$a= (3.14)* (2.5 \ ft)^2$

Solve the exponent.

(2.5 ft)²= 2.5 ft *2.5 ft=6.25 ft²

$a= (3.14)*(6.25 \ ft^2)$

Multiply.

$a=19.625 \ ft^2$

The area of the circle is 19.625 square feet.

4 0

3 years ago

Suppose that 60 percent of customers at a McDonalds purchase a hamburger, and assume that the purchases of different customers a

Alborosie

Answer:

a) 83.87% probability that at most 7 of the next 10 customers will order a hamburger.

b) 25.08% probability that exactly 6 of the next 10 customers will order a hamburger

Step-by-step explanation:

For each customer at McDonalds, there are only two possible outcomes. Either they purchase a hamburguer, or they do not. The purchases of different customers are independent. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

60 percent of customers at a McDonalds purchase a hamburger

This means that $p = 0.6$

a) What is the probability that at most 7 of the next 10 customers will order a hamburger? (3 POINTS).

This is $P(X \leq 7)$ when n = 10.

We know that either at most 7 of the next customers will order a hamburguer, or more than 7 will. The sum of these probabilities is decimal 1. So

$P(X \leq 7) + P(X > 7) = 1$

$P(X \leq 7) = 1 - P(X > 7)$

In which

$P(X > 7) = P(X = 8) + P(X = 9) + P(X = 10)$

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 8) = C_{10,8}.(0.6)^{8}.(0.4)^{2} = 0.1209$

$P(X = 9) = C_{10,9}.(0.6)^{9}.(0.4)^{1} = 0.0403$

$P(X = 10) = C_{10,10}.(0.6)^{10}.(0.4)^{0} = 0.0001$

$P(X > 7) = P(X = 8) + P(X = 9) + P(X = 10) = 0.1209 + 0.0403 + 0.0001 = 0.1613$

$P(X \leq 7) = 1 - P(X > 7) = 1 - 0.1613 = 0.8387$

83.87% probability that at most 7 of the next 10 customers will order a hamburger.

b) What is the probability that exactly 6 of the next 10 customers will order a hamburger? (3 POINTS)

This is P(X = 6).

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 6) = C_{10,6}.(0.6)^{6}.(0.4)^{4} = 0.2508$

25.08% probability that exactly 6 of the next 10 customers will order a hamburger

7 0

3 years ago