Find the surface area of a cube with edges 6.57 cm long.

Tenemos 2 rectangulos, el primero mide 15 centimetros de largo y 4 centimetros de ancho al formar el segundo rectangulo se dupli

sergey [27]

Answer:

El segundo rectangulo va medir 30 centimetros de largo y 8 centimetros de ancho.

Step-by-step explanation:

Duplicar las medidas significa que vamos multiplicar las medidas por 2.

15 cm × 2= 30 cm

4 cm × 2= 8 cm

Espero que te ayude!

8 0

3 years ago

WILL MARK BRAINLIEST!! 5 POINTS!!

Anton [14]

The speed of the car per minute is 3,520 feet (choice c). This is because in order to solve the problem, you have to convert 40 mi/h into feet. Since there are 5,280 feet per mile, you have to do 5,280 x 40, which is 211,200, which is the number of feet per hour. But, the question is asking for ft/min. There are 60 minutes in an hour, so you divide 211,200 by 60, which is 3,520. So, the speed of the car per minute is 3,520 feet.

5 0

3 years ago

Read 2 more answers

Please tell me if I got this one right or not

Lunna [17]

Answer:no

the answer is c

Step-by-step explanation:

3 0

2 years ago

Read 2 more answers

A 500-gallon tank initially contains 220 gallons of pure distilled water. Brine containing 5 pounds of salt per gallon flows int

Wittaler [7]

Answer: The amount of salt in the tank after 8 minutes is 36.52 pounds.

Step-by-step explanation:

Salt in the tank is modelled by the Principle of Mass Conservation, which states:

(Salt mass rate per unit time to the tank) - (Salt mass per unit time from the tank) = (Salt accumulation rate of the tank)

Flow is measured as the product of salt concentration and flow. A well stirred mixture means that salt concentrations within tank and in the output mass flow are the same. Inflow salt concentration remains constant. Hence:

$c_{0} \cdot f_{in} - c(t) \cdot f_{out} = \frac{d(V_{tank}(t) \cdot c(t))}{dt}$

By expanding the previous equation:

$c_{0} \cdot f_{in} - c(t) \cdot f_{out} = V_{tank}(t) \cdot \frac{dc(t)}{dt} + \frac{dV_{tank}(t)}{dt} \cdot c(t)$

The tank capacity and capacity rate of change given in gallons and gallons per minute are, respectivelly:

$V_{tank} = 220\\\frac{dV_{tank}(t)}{dt} = 0$

Since there is no accumulation within the tank, expression is simplified to this:

$c_{0} \cdot f_{in} - c(t) \cdot f_{out} = V_{tank}(t) \cdot \frac{dc(t)}{dt}$

By rearranging the expression, it is noticed the presence of a First-Order Non-Homogeneous Linear Ordinary Differential Equation:

$V_{tank} \cdot \frac{dc(t)}{dt} + f_{out} \cdot c(t) = c_0 \cdot f_{in}$ , where $c(0) = 0 \frac{pounds}{gallon}$ .

$\frac{dc(t)}{dt} + \frac{f_{out}}{V_{tank}} \cdot c(t) = \frac{c_0}{V_{tank}} \cdot f_{in}$

The solution of this equation is:

$c(t) = \frac{c_{0}}{f_{out}} \cdot ({1-e^{-\frac{f_{out}}{V_{tank}}\cdot t }})$

The salt concentration after 8 minutes is:

$c(8) = 0.166 \frac{pounds}{gallon}$

The instantaneous amount of salt in the tank is:

$m_{salt} = (0.166 \frac{pounds}{gallon}) \cdot (220 gallons)\\m_{salt} = 36.52 pounds$

3 0

3 years ago

Find (f∘g)(x) if f(x) = 2x - 1 and g(x) = x + 2. A.2x - 3 B.2x + 1 C.2x - 1 D.2x + 3

V125BC [204]

(f∘g)(x) = f(g(x)) = f(x +2)
= 2(x +2) -1
= 2x +3 . . . . . selection D

5 0

3 years ago