Mathematics, 02.08.2021 21:00, angeline2004

Can someone please help me with these 3 questions?

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answered: lexie2439

25) First, find the amount of minutes in 2 hours. Note that there are 60 minutes in one hour:

2 x 60 = 120 minutes per 2 hours.

Next, the bacteria doubles every 20 minutes. 120/20 = 6, which means that the bacteria will double 6 times:

1 x 2 = 2

2 x 2 = 4

4 x 2 = 8

8 x 2 = 16

16 x 2 = 32

32 x 2 = 64

64 bacteria will be your answer.

26) The Area of a circle = πr²

Set the equation:

400π = π(r + 2)²

First, divide common factors from both sides, or π.

(400π)/π = (π(r + 2)²)/π

400 = (r + 2)²

√400 = √(r + 2)²

r + 2 = √400

r + 2 = √(20 x 20)

r + 2 = 20

r + 2 (-2) = 20 (-2)

r = 20 - 2

r = 18

18 is your final answer.

27)

The volume of a box can be found by multiplying length x width x height:

V (box) = l * w * h

The volume given is 90, the height 3, and the width is 1 foot less then length:

First solve what you know:

$V(box) = 90\\h = 3\\l = l\\w = l - 1$

Plug in the corresponding terms with the corresponding variable. Isolate the variable, l. Divide 3 from both sides of the equation:

$90 = 3 * l (l - 1)\\\frac{90}{3} = \frac{3 * l(l -1)}{3}\\30 = l(l - 1)\\$

Distribute l to both terms in the parenthesis:

$30 = l(l - 1)\\30 = l^2 - l$

Solve:

$30 = (6)^{2} -6\\30 = 36 - 6\\30 = 30$

∴ l = 6

Solve for width. Width is 1 less foot then length:

$l - 1 = w\\l = 6\\$

∴ $6 - 1 = w\\w = 5$

Equation: V (box) = l * w * h

$l = \frac{V(box)}{w * h}$

$V(box) = 90\\h = 3\\l = 6\\w = 5$

answered: Guest

"it's not the heat, it's the humidity". that's a partly valid phrase you may have heard in the summer, but it's actually both. the heat index, also known as the apparent temperature, is what the temperature feels like to the human body when relative humidity is combined with the air temperature. this has important considerations for the human body's comfort. when the body gets too hot, it begins to perspire or sweat to cool itself off. if the perspiration is not able to evaporate, the body cannot regulate its temperature. evaporation is a cooling process. when perspiration is evaporated off the body, it effectively reduces the body's temperature. when the atmospheric moisture content (i.e. relative humidity) is high, the rate of perspiration from the body decreases. in other words, the human body feels warmer in humid conditions. the opposite is true when the relative humidity decreases because the rate of perspiration increases. the body actually feels cooler in arid conditions. there is direct relationship between the air temperature and relative humidity and the heat index, meaning as the air temperature and relative humidity increase (decrease), the heat index increases (decreases).

step-by-step explanation: