# Posts by Theo

Total # Posts: 44

**chemistry**

A hypothetical element has two main isotopes with mass numbers of 71 and 74. If 80.00% of the isotopes have a mass number of 71 amu, what atomic weight should be listed on the periodic table for this element? (answer in AMU).

**Thermodynamics/ Energy**

Determine the effects of compression ratio on the net work output and the thermal efficiency of the Otto cycle for a maximum cycle temperature of 2000 K. Take the working fluid to be air that is at 100 kPa and 300 K at the beginning of the compression process, and assume ...

**Math**

Here it just says this: Solve triangle ABC. (If an answer does not exist, enter DNE. Round your answers to one decimal place.) b = 67, c = 33, ∠A = 70°

**physics**

A uniform circular disk of mass 24.0 g and radius 40.0 cm hangs vertically from a fixed, frictionless, horizontal hinge at a point on its circumference. A horizontal beam of electromagnetic radiation with intensity 10.0 MW/m2 is incident on the disk in a direction ...

**chemistry**

64.1

**Math**

Write down two unitary fractions whose difference is 1/40

**Literature**

(Ethan Frome by Edith Wharton) discuss whartons use of short flashbacks. why are they placed where they are?

**Physics - test question verification**

Forces of 2.4 N and 1.8 N act on an object at right angles to one another. What is the magnitude of a third force acting on the same object so that it remains stationary? A) 3.0 N B) 4.2 N C) 0.6 N I don't understand how the answer is A)

**Math**

"If a quadrilateral is a rectangle, then it is a parallelogram." i) is the converse true? ii) is the inverse true? iii) is the contrapositive true?

**Math**

Thanks Steve!

**Math**

If you are given a conditional statement that you know is true, can you predict whether i) the converse is true? ii) the inverse is true? iii) the contrapositive is true?

**business,maths lit tourism economics**

can i be a lawyer?

**math**

15x^2-102x=3 _____________ 7

**life orientation**

what are 10 ways in which environmental health hazards impact negatively in one's life

**maths literacy,business studies, tourism, economic**

lawyer

**Math**

mmmmmmmmm....

**Physics**

t = sqrt(2h/9.8) 0.447s = 0.452 H H = 0.988 now find the angle, use your calculator and plug in arctan (0.988 / 2.37 ) should be 22.6 degrees.

**Math**

I came up with 23%. Correct?

**Math**

If 72% of Americans have straight hair, 76% have brown eyes, 87% are high school graduates, and 88% are less than 6 feet tall, what is the minimum percentage of Americans who have all four attributes?

**Math**

Sam rolls a standard die, and then Ruth rolls the same die. The probability that Ruth's number is higher than Sam's can be written as a/b where a and b have no common factors greater than 1. Find a.

**english**

What public health issue starts the escalation of misery in "top of the food chain"?

**trig**

Solve system of inequalities by graphing Y<2-x Y>x+4

**math**

the area of a circle inscribed in the triangle formed by the line with equation x+y=1 and the two coordinate axes can be written in the form pi(a+b(sqr.c)/d) compute the value of a+b+c+d

**Math**

The capital letter F can be formed by connecting the points (0,4)(5,4) (5,2)(2,2) (2,0) (4,0) (4,-2) (2,-2) (2,-7) nad (0,-7), in this order. Determine the slope of a line that passes through the origin and divides the letter F into two regions of equal area.

**math**

The numbers 38, x, -8, and y form an arithmetic sequence. Compute x+y

**Math**

The product of three consecutive odd integers reduced by 23 is 99 less than the cube of the sum of the smallest number and 2. Compute the mean of the three integers.

**Life orientation**

Yes

**chemistry**

What is the new volume if the volume of a gas is 3.2 L when the temperature is 7 C if the temperature is increased to 15 C without changing the pressure

**calculus**

Calculate the derivative of the function. Then find the value of the derivative as specified. f(x) = 8/(x+2); f '(0)

**calculus**

A piece of land is shaped like a right triangle. Two people start at the right angle at the same time, and walk at the same speed along different legs of the triangle while spraying the land. If the area covered is changing at 4m^2/s how fast are the people moving when they ...

**calculus**

Calculate dy/dt using the given information. (x+y)/(x-y)= x^2 + y^2; dx/dt = 12, x = 1, y = 0

**calculus**

A company knows that unit cost C and unit revenue R from the production and sale of x units are related by R^2/236000+5507 . Find the rate of change of revenue per unit when the cost per unit is changing by and the revenue is

**calculus**

A heart attack victim is given a blood vessel dilator to increase the radii of the blood vessels. After receiving the dilator, the radii of the affected blood vessels increase at about 1% per minute. According to Poiseulle's law, the volume of blood flowing through a ...

**calculus**

Calculate dy/dt using the given information. (x+y)/(x-y)= x^2 + y^2; dx/dt = 12, x = 1, y = 0?

**calculus**

Calculate dy/dt using the given information. xy + x = 12; dx/dt = -3, x = 2, y = 5?

**math**

y = (x-6)(x^2+2x) all over x^3

**calculus**

Find the derivative of the function. h(x) = (cos x/ 1+sin x)4

**calculus**

Find the derivative of the function. y = cos^4(¹t - 8)

**History**

What makes 1890-1920 the nadir of race elections? I am doing my History study guide, and they just randomly popped that question in there--i don't even know what it means, and we CERTAINLY never learned it in class!

**History**

What is the Dakota War of 1862 so important?

**Chemistry**

.3mol b.404g

**English**

Thank you, Ms. Sue. The site was very helpful.

**English**

In the book, Language in Thought and Action 5th edition, by S.I and Alan Hayakawa, what are the main principles? I have a few already: 1)Cooperation is essential in order to have a society. 2)Words aren't the only thing associated with language: tone of voice, rhythm, and ...

**Physics**

(a). 58.8joules (b).0joules