1. Physics Gravity

A projected space station consists of a circular tube that will rotate about its center (like a tubular bicycle tire) as shown in the figure . The circle formed by the tube has a diameter of about 1.1-km g = R w^2 = 9,8 m/s^2 R = 550 m How do I convert the

2. physics

A 0.40kg ball, attached to the end of a horizontal cord, is rotated in a circle of radius 2.1m on a frictionless horizontal surface.If the cord will break when the tension in it exceeds 80N , what is the maximum speed the ball can have?

3. chemistry

I have: the half life of U-238 is 4.5 x 10^9 yr. A sample of rock of mass 1.6g produces 29 disintegrations per second. find percent by mass of U-238 in rock. I have 4.5x 10^9x60x60x365x24=1.419x 10^17= .693/1.419 x10^17 =4.883x10^-18 =rate 1.6/238=.006722

4. Physics

How much energy is required to move a 900 kg object from the Earth's surface to an altitude twice the Earth's radius?

5. math

A car has a 12 volt battery. The engine has a resistance of 0.22 ohms. How many amps will be drawn from the battery when the key is turned?

6. Chemistry

How much heat is liberated when 0.113 mole of sodium reacts with excess water according to the following equation? DH = -368 kJ/mol rxn

7. math

This is confusing: This proportion can be changed to (0.45)y = x, where x represents the person's weight in kilograms and y represents the person's weight in pounds. The recommended protein in grams is numerically equal to the person's weight in kilograms.

8. chemistry

Calculate the concentrations of all species in a 1.67 M Na2SO3 (sodium sulfite) solution. The ionization constants for sulfurous acid are Ka1 = 1.4× 10–2 and Ka2 = 6.3× 10–8. I know how to find the Na^+ and SO3^-2 but I don't know how to find

9. chemistry

A 1.50 liter gas sample at 745mm HG and 25 celsius contains 3.55% radon by volume radon-220 is an alpha emitter with a half life of 55.6 seconds. how many alpha particles are emitted in 5 minutes by this sample? I got an answer 1.59x10^19 I started at

10. Chemsitry

Use these data to estimate Avogadro's number. Palladium crystallizes with a face-centered cubic structure. It has a density of 12.0g/cm^3 , a radius of 138 pm , and a molar mass of 106.42 g/mol .

11. math

You must cover a hole that is elliptical in shape. You measure the major and minor axes and find them to be 6 ft. and 4.5 ft. respectively. If you want a 6 inch overhang around the hole, how much covering will you need? (Round to the tenths place.)

12. Physics

A 1400 kg car rounds a curve of 57 m banked at an angle of 14 degree If the car is traveling at 98 km/h, how much friction force will be required? I cannot figure out how to solve this problem. Someone please help me?

13. Physics

Planet Jupiter revolves around the Sunin 12 years (3.79 X 10^8 sec. What is its mean distance from center of Sun? mass of sun is 1.99 x 10^30 kg.

14. science

an arrow is shot into air. its range is 200m and its time of flight is 5s . if g=10m/s2 ,then horizontl compoent of velocity and the mximum height will be

15. Chemistry

In the following experiment, a coffee-cup calorimeter containing 100 \rm mL of \rm H_2O is used. The initial temperature of the calorimeter is 23.0 \rm ^{\circ}C. If 9.80 g of \rm CaCl_2 is added to the calorimeter, what will be the final temperature of

16. Finance

Aset P has a beta of 0.9. The risk-free rate of return is 8%, while the return on the S&P 500 is 14%. Asset P's required rate of return is:

17. Physics

A 3.30-kN piano is lifted by three workers at a constant speed to an apartment 28.8 m above the street using a pulley system fastened to the roof of the building. Each worker is able to deliver 197 W of power, and the pulley system is 75.0% efficient (so

18. math

what percent of 67 is 33? round to the nearest tenth of a percent. the answer is 49.3% but i don't know how he got that can you explain

19. Beginner Alegra

From a point on a straight road, Nico and Maria are riding bicycles in the same direction. Nico rides at 12mph and Maria rides at 14mph. In how many hours will they be 11 mi apart?

20. physics

a source of sound id traveling towards a stationary observer .The frequency of sound is heard by the observer is 25% more that the actual frequency.If the speed of sound is v,that of the source is options: 1.v/4 2.v/5

21. Physics help!!!

What potential difference is required in an electron microscope to give electrons a wavelength of 0.05 nm ?

22. Math

A square garden plot measures 180 square feet. A second square garden plot measures 405 square feet. How many more feet of fence will the second garden plot require over that required for the first garden plot. But how did they get this???????

23. physics

a gun is fired from a distance of 1.2 km from a hill.the echo of the sound is heard after 7.1 seconds at the same place. Calculate the velocity of sound.

24. physics

to an observer the pitch of the stationary source of the sound appears to be reduced by 20% if speed of sound is 340m/s then sped and direction of 5he observer is options 1.68 m/s away from the observer 2.96 m/s away from the observer

25. physics

Find the temperature at which the velocity of sound in air is 1.25 times the velocity of sound at 0 degree centigrade.

26. Physics

What is the maximum speed with which a 1150-kg car can round a turn of radius 71 m on a flat road if the coefficient of static friction between tires and road is 0.80? May someone walk me through this problem step by step? Thank you *The equation friction

27. Physics ( light)

A student doing Young's experiment measures a distance of 6.0 cm between the first and seventh nodal points on a screen located 3.0 m from the slit plate. a) if the slit seperation is 220^ -6, what is the wave length of light being used ? b) what colour is

From a window in apartment building the angle of evaluation from the top of the flag pole across the street is 9 degrees. The angle of depression is 22 to the base of flag. How tall is flag pole to the nearest of tenth meter?

64. Calculus

y=cos3x(sin^3)x

65. Algebra

I need help doing this problem, should I not get the same answer with each technique? Please help. What three techniques can be used to solve a quadratic equation? Demonstrate these techniques on the equation: 2x² + 3x + 1 = 0

104. word choices

Did you win or (loose or lose) the game?

105. physical Edu

Identify the effects of MDMA: a. can result in a heat stroke b. can cause dehydration c. increases heart rate and blood pressure d. increases feelings of closeness e. all of the above can be effects of MDMA use. is it C

106. Chemistry

Will someone please help me? I had a question and i answered it, but i coudn't draw a picture for it. Can some help me draw a picture for it or tell me how to draw it step by step. Thank you. The nucleus is made up of protons and neutrons. Protons and

107. Geometry

I need help with these problems: 11. The 2 captains of the school football team meet with the 3 captains of another team for the coin toss. If each captain shakes hands with each captain from the opposing team, how many different handshakes occur? 14. Find

108. Mergers and Acquisitions

List any three of the reasons why the firm would continue to exist beyond the point where its products have become obsolete.

109. Mergers and Acquisitions

Why did M & A activity decrease in the late 1980s and early 1990s? Why did M & A activity increase again in the latter part of the 1990s?

110. physics

in a hypothetical thermometer, the freezing point of water is marked as -10 and the boiling point is marked at 70. What would be the reading if this thermometer is used to measure the temperature of 50 degree water?

111. science

what animals don't have a circulatory system. please answer fast thank you

112. Chemistry

The density of a liquid is 3.22 g/mL. How many milliliters are there in 2.62 kg? If you answer this could you give me an explanation of how to solve it in the future

Would you invest in the company you reviewed based on the information contained in the annual report? Why or why not? Please list examples to support your answer.

114. algebra

How many units were produced in APRIL? What is the length of the rod AB to the nearest quarter inch?

115. Math

Graph the equation X = 1/2 y2

116. Math

Graph the line Y = 5x + 6

117. english

1. There should be commas around “however” in the following sentence: “Dwayne had planned to take the last flight out to Chicago. It was cancelled, however, because of bad weather.” (Points : 1) True False

118. math

I need help with this problem: finding the instantaneous rate of change of y with respect to x at the point x=5 if y=x^2/2+3/5x-1 I know I am suppose to find the determinant first then plug in 5...but I am not sure about the determinant

119. math

complete these series,1,8,27,64,___,____

120. math

complete these series,1,8,27,64,___,____

121. logic

If P is true, and Q is false, the truth-value of "P v Q" is

122. Foreign languages

Writeacher, could you please check these sentences? Thank you. 1) I'm forwarding you the link to the requirements for next year's Comenius exchange programme. I really hope to receive some good news from you. 2) We are looking for a hotel accommodation for

123. Math

how do you solve: 4=1(2)/(x-2) Thank you!

124. Physics

Why "weighing" individual atoms is a particular challenge? Using A small beam arranged as a cantilever, can be utilized as part of a sensing device.

125. prealgebra

Evaluate showing work (23 - 3) ÷ (-5)

126. pre algebra

(0.43 - 0.18) X 4 evaluate please show how its done

127. pre algebra

11 - 8 ÷ (1/3 + 1/5) Please show work I am stuck. Thank you

128. math

11 - 8 ÷ (1/3 + 1/5) I need to know how to to this please show me. Thank you

129. Art

Who is the artist of the Ngady Mwaash Mask (search on yah oo, then click images, it should be the 4th one) and the artist of the Sowo Mask, (same thing, go to yah oo search the name then click images, and it should be the 1st one)

130. Algebra

I'm having a problem dividing 2x^3 - x^2 + 3x -1) ÷ (x + 2)

131. English

What are three characteristics of a good paragraph? THANK YOU

132. Chemistry

What concentration of aqueous NaOH solution freezes at negative 3.2 degrees celsius ?

133. Mergers and Acquisitions

Define a horizontal merger. How can a horizontal merger produce synergy benefits?

134. Mergers and Acquisitions

List the three ways that tender offer legislation protects target company shareholders?