Ask question

Ask question

All categories

1 year ago

7

Can some one help me with this question its hard :( down below ill give brainliest

1 answer:

vova2212 [387]1 year ago

7 0

Answer:

c

Step-by-step explanation:

You might be interested in

Whats the perimeter and area of this shape?

stich3 [128]

Answer:

<u>60+14.35=88.27</u>

Step-by-step explanation:

5x12 for the rectangle on the right, then for the circle, using the formula A=πr², I get 28.27, which you divide by 2 because you only need half of the circle, and you get 88.27. I calculated the radius by subtracting 12-6 and then dividing that in half because the radius is half of the distance to the other end of the circle. Then you get the radius of 3, then plug it into the formula to get π(3)², which is just 3.14(9), and you get 28.27.

8 0

2 years ago

Read 2 more answers

Which statement is true

Jet001 [13]

Answer:

A

Step-by-step explanation:

using common sense you can see that the angle of c is obtuse and it would need to be smaller than angles a and b

4 0

2 years ago

PLZ ANSWER THIS<br> thanksssss

just olya [345]

Answer:

It should be C) 11+ 3 5/8

Step-by-step explanation:

5 0

2 years ago

Which statements are true about the circle shown below? Select two options.

sineoko [7]

Answer:

C and D

Step-by-step explanation:

4 0

2 years ago

A tank initially contains 60 gallons of brine, with 30 pounds of salt in solution. Pure water runs into the tank at 3 gallons pe

adoni [48]

Answer:

the amount of time until 23 pounds of salt remain in the tank is 0.088 minutes.

Step-by-step explanation:

The variation of the concentration of salt can be expressed as:

$\frac{dC}{dt}=Ci*Qi-Co*Qo$

being

C1: the concentration of salt in the inflow

Qi: the flow entering the tank

C2: the concentration leaving the tank (the same concentration that is in every part of the tank at that moment)

Qo: the flow going out of the tank.

With no salt in the inflow (C1=0), the equation can be reduced to

$\frac{dC}{dt}=-Co*Qo$

Rearranging the equation, it becomes

$\frac{dC}{C}=-Qo*dt$

Integrating both sides

$\int\frac{dC}{C}=\int-Qo*dt\\ln(\abs{C})+x1=-Qo*t+x2\\ln(\abs{C})=-Qo*t+x\\C=exp^{-Qo*t+x}$

It is known that the concentration at t=0 is 30 pounds in 60 gallons, so C(0) is 0.5 pounds/gallon.

$C(0)=exp^{-Qo*0+x}=0.5\\exp^{x} =0.5\\x=ln(0.5)=-0.693\\$

The final equation for the concentration of salt at any given time is

$C=exp^{-3*t-0.693}$

To answer how long it will be until there are 23 pounds of salt in the tank, we can use the last equation:

$C=exp^{-3*t-0.693}\\(23/60)=exp^{-3*t-0.693}\\ln(23/60)=-3*t-0.693\\t=-\frac{ln(23/60)+0.693}{3}=-\frac{-0.959+0.693}{3}= -\frac{-0.266}{3}=0.088$

5 0

2 years ago