# Posts by bert

Total # Posts: 37

**Math**

$20

**physics**

a uniform beam with a weight of 51.3 N and a length of 3.23 m is hinged at its lower end, and a horizontal force Upper F Overscript right-arrow EndScripts of magnitude 64.0 N acts at its upper end. The beam is held vertical by a cable that makes angle θ = 20.7° with ...

**Statistics**

10. A teacher gives 200 students a study guide for a test and the average score was 90 with a standard deviation of 6. She did not give the other 200 students a study guide and their average score was 70 with a standard deviation of 8. Find the critical value to determine ...

**Statistics**

10. A teacher gives 200 students a study guide for a test and the average score was 90 with a standard deviation of 6. She did not give the other 200 students a study guide and their average score was 70 with a standard deviation of 8. Find the critical value to determine ...

**Physics**

Two cars are parked on a street. A third car hits the back of the second car and causes all of the cars to move. (Ignore the distance between the cars). Calculate: (a)The acceleration of the whole system; (b)the net force on each car; (c)the contact force that each car exerts ...

**Physics**

A mountain climber dangles his water bottle and feels the bottle makes an angle of 25 degrees with respect to the vertical line. If his acceleration takes 18 seconds, calculate the speed of the climber.

**math**

Together, Misty and Keith caught 29 fish. Keith caught 5 fewer fish than Misty. How many did they each catch?

**Physics**

If the critical frequency of a low-pass filter is 5 kHz, what is the filter bandwidth?

**Physics**

If the two input voltages to a 2-input summing amplifier are +2 V and +5 V, what is the output voltage?

**Algrebra-Systems of Equations**

54

**Chemistry**

A certain shade of blue had a frequency of 1.01*10^-4 Hz. What is the energy of exactly one photon of this light?

**Chemistry**

50 ml of 5 M H2SO4 react with excess BaCl2 to Make 40 g of BaSO4. a.) What is the theoretical yield of BaSO4? b.) What is the Percentage yield of BaSO4

**Science**

Is the answer 26 celsius? Is it possible that the temp is greater than 25 celsius? A 500 mL bottle of water, which is at 25 degrees C, is poured over 120 g of ice at -8 degrees C. What will be the final temperature of the water when all the ice has melted. Assume that ...

**Science**

Does c in the equation stand for temperature in celsius?

**Science**

A 500 mL bottle of water, which is at 25 degrees C, is poured over 120 g of ice at -8 degrees C. What will be the final temperature of the water when all the ice has melted. Assume that container is insulated and does not change temperature.

**Science**

Does c stand for temperature in celsius?

**Science**

What do Tf and Hf stand for? Are they constants? Also, is Tf different from tf?

**Science**

A 500 mL bottle of water, which is at 25 degrees C, is poured over 120 g of ice at -8 degrees C. What will be the final temperature of the water when all the ice has melted. Assume that container is insulated and does not change temperature.

**Statistics**

When circuit boards used in the manufacture of compact disc players are tested, it is discovered that each has a 5% chance of being defective. Suppose that a batch of 25 of these circuit boards is randomly selected. Would this be binomial or poission distribution?

**math**

Write to least to greatest. 45/6, 7 1/3 , 7, 4

**differential geometry**

given a circle in S^2 with radius p in the spherical metric, show its area is 2pi(1-cos p)

**bio**

Transformation efficiency = (Total number of cells growing on the agar plate) / (Amount of DNA spread on the agar plate (in µg)). So if the transformation efficiency is 4 x 10^3 and the amount of plasmid on the plate is 0.04 micrograms, then: 4 x 10^3 = x / 0.04 ...

**physics**

36.75

**Cell Biology**

What is the theoretical limit of resolution in micrometers when there is a numerical aperture (N.A) of 0.10, 500nm wavelength, and 4X magnification?

**Organic Chem**

NaCl was used to rinse a condenser after distillation of 4-methylcyclohexene to remove unreacted phosphoric acid. Why is saturated NaCl used to rinse the glassware rather than water?

**Organic Chemistry**

What major product is formed by the dehydration of 1,2-cyclohexanediol (consider keto-enol tautomerism)?

**Organic Chemistry**

HCl is added to t-pentyl alcohol in a vial to synthesize t-pentyl chloride. t-pentyl chloride separates on top and the bottom layer is discarded. Sodium bicarbonate is then used to wash the crude t-pentyl chloride. What is the purpose of this wash and why would it be bad to ...

**MATH!!!!!!!**

The river boat paddled upstream at 12km/h, stopped for 2 h of sightseeing, and paddled back at 18km/h. How far upstream did the boat travel if the total time for the trip, including the stop, was 7h? Please help me, the answer is 36 km but i have no idea how to set it up

**chemisty**

Consider the titration of 50 mL of 0.15 M NH3 with 0.1 M HCl. What is the pH at the equivalence point of the titration? (Kb= 1.8X 10-5 Ka= 5.6X10-10)

**Math**

The numbers are 45 and 7, how do you calculate the ratio?

**History**

Could it be described as the state taking total control over the church by determining how the church will function? I was thinking that after the Roman Empire established Christianity the primary religion that the state was able to over-rule and control the Catholic church. ...

**History**

What was the relationship between church and state during the 16th Protestent Reformation?

**Chemistry**

I don't understand where the H+ comes from, I mean I know it comes from the acid, but don't I need an equilibrium constant K to solve for the H+?

**Chemistry**

If 100mL of a 0.10M NaOH solution is added to 75mL of a 0.15 HCl solution, then what is the pH of the resultant solution?

**History**

During the 16th century protestent reformation, what was the relationship between the church and state? http://en.wikipedia.org/wiki/Protestant_reformation Let us know what you conclude, and someone here will be able to critique your thinking. =)

**Physics**

If a solid glass cylinder is placed above the words Lead Oxide (Lead in red print and Oxide in blue) and viewed from the side, the word Lead appears inverted, but the word Oxide does not. Explain. What part of the cylinder is on top of the letters? From what direction is it ...

**Physics**

Suppose you are told that only two colors of light (X and Y) are sent through a glass prism and that X is bent more than Y. Which color travels more slowly in the prism? The one that is bent more travels slower. If white light is sent through a prism, the colors on the other ...