1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
djyliett [7]
3 years ago
9

Please help me!!!!!!!!!!!

Mathematics
1 answer:
alex41 [277]3 years ago
5 0
A is 4/9 B is 4/15 C is 8/5 D is 3/10
You might be interested in
Half-life of Po-210 is 140 days. If the initial mass of the sample is 5
Anna35 [415]

Answer:

0.625kg

Step-by-step explanation:

we are given half-life of PO-210 and the initial mass

we want to figure out the remaining mass <u>after</u><u> </u><u>4</u><u>2</u><u>0</u><u> </u><u>days</u><u> </u>

in order to solve so we can consider the half-life formula given by

\displaystyle f(t) = a {0.5}^{t/T}

where:

  • f(t) is the remaining quantity of a substance after time t has elapsed.
  • a is the initial quantity of this substance.
  • T is the half-life

since it halves every 140 days our T is 140 and t is 420. as the initial mass of the sample is 5 our a is 5

thus substitute:

\displaystyle f(420)=5\cdot{0.5}^{420/140}

reduce fraction:

\displaystyle f(420)=5\cdot{0.5}^{3}

By using calculator we acquire:

\displaystyle f(420)=0.625

hence, the remaining sample after 420 days is 0.625 kg

4 0
3 years ago
Mathew’s mom asked him to go to the store for her. To get to the store he walked seven blocks. He caught the bus and rode 13 blo
SVETLANKA909090 [29]

7+13+1.5=21.5

If he did it again the way back, it's 21.5 times 2.

He went a total of 43 blocks.

6 0
3 years ago
Read 2 more answers
Professor wonders whether a student's homework average (X) could be used to predict their final grade in the course (Y) . She ca
Anna11 [10]

Answer:

The dependent variable is the final grade in the course and is the vriable of interest on this case.

H0: \beta_1 = 0

H1: \beta_1 \neq 0

And if we reject the null hypothesis we can conclude that we have a significant relationship between the two variables analyzed.

Step-by-step explanation:

On this case w ehave the following linear model:

Y= 21.839 +0.724 X

Where Y represent the final grade in the course and X the student's homework average. For this linear model the slope is given by \beta_1 = 0.724 and the intercept is \beta_0 = 21.839

Which is the dependent variable, and why?

The dependent variable is the final grade in the course and is the vriable of interest on this case.

Based on the material taught in this course, which of the following is the most appropriate alternative hypothesis to use for resolving this question?

Since we conduct a regression the hypothesis of interest are:

H0: \beta_1 = 0

H1: \beta_1 \neq 0

And if we reject the null hypothesis we can conclude that we have a significant relationship between the two variables analyzed.

3 0
3 years ago
Please help me with this D:
I am Lyosha [343]
Yes, because 120 - 36 = (120\times 36) - 4236 = 84

Hope that helped :D
8 0
3 years ago
Hi can someone help me with this
Ad libitum [116K]

Answer:

25 units

Step-by-step explanation:

Applying Pythagoras' Theorem,

(BD)^2= (CD)^2 + (BC)^2

(BC)^2= 65^2 - 60^2

(BC)^2= 625

BC= √625= 25

5 0
3 years ago
Other questions:
  • Marisa Thinks she can afford 11 movies in one month.What mistake could she be making
    15·1 answer
  • What’s the value of 2 quarters 4 dimes and 6 pennies
    11·2 answers
  • Which graph shows Point P as (–5,6) and Point Q as (3,–4)?
    14·2 answers
  • Which algebraic expression is represented by the model?
    14·1 answer
  • What is the area of the trapezoid shown below?
    11·2 answers
  • The following table represents the highest educational attainment of all adult residents in a certain town. If a resident who is
    9·1 answer
  • Please help me with this
    5·1 answer
  • Solve for x:<br> 2x + 9 = 3
    15·2 answers
  • Someone please help me. Im giving brainliest!!
    12·2 answers
  • Identify the inequality that describes this graph​
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!