Total # Posts: 3,229
Fossil Occurrence and the Age of Rocks: Groups of fossil organisms occur throughout the geologic record for specific intervals of time. This time interval is called the fossils range. Knowing the range of the fossils of specific organisms or groups of organisms can be ...
June 6, 2016
Why Devonian could not be considered an index fossils? How can the occurrence of fossils and their known age ranges be used to date rocks? Need help by understanding the question.
June 6, 2016
Math ~ CHECK ANSWER
Below are two sets of student quiz scores on a 30-point quiz. Which of the following can you conclude by comparing their box-and-whisker plots? Class A: 5, 10, 13, 18, 19, 25, 29 Class B: 1, 3, 5, 7, 9, 9, 13 a) The first quartile of class B is greater than the third quartile ...
June 2, 2016
In a certain experiment, the rate constant, k, was measured as a function of the temperature, T. Two data points were as follows: (A) 25°C, 1.1 x 105 min1, and (B) 225°C, 2.4 x 10-2 min1. The student who performed the experiment then ...
June 1, 2016
At 425°C, a reaction has a rate constant of 7.7 x 104 s1 and has an activation energy of 275 kJ mol1. What is the frequency factor? The answer is 2.9 x 1017 s1 , I need help with working out I used arrhenius equation and rearranged ...
June 1, 2016
In a marathon race, Chad is out in front, running due north at a speed of 3.92 m/s. John is 94 m behind him, running due north at a speed of 4.33 m/s. How long does it take for John to pass Chad
May 23, 2016
#1) which digit is 10 times the value in the underline digit in 36,119,432 (#that is underline is number 1 between the 1 and 9 ) I think the answer is one hundred thousand #2) which digit is 1/1000 of the value in the underline digit in 19,832,456 (# underline is 3) My answer ...
May 20, 2016
#1) Luis stated that when you are converting meters to centimeters your answer will be larger than your original number. My answer is yes because centimeters are smaller . (Is my answer OK ) #2) 8/9 + 1/3= 33/27= 1(12/27)= (I'm stuck here) #3) 6/8-2/6=2 (18/20) =2 (9/10) ...
May 20, 2016
single most powerful European political ideology of the 19th and early 20th centuries political outlook, nationalism was and is based on the relatively modern concept that a nation is composed of people who are joined together by the bonds of common language as well as common ...
May 19, 2016
A model rocket is launced from the ground with an initial velocity of 65 m/s directly upwards. If a horizontal wind is blowing at 5 m/s during the flight, how far from the launch point will the rocket land? I know I should probably be using the equation x=x0+v0t+1/2at^2, but i...
May 12, 2016
How many gram of sodium fluoride should be added to 100000 liter of drinking water containing 0.6 ppm of sodium fluoride to provide a recommended concentration of 1.75 ppm? Answer is 115 grams. I keep getting .115 g What am I doing wrong? Please help.
May 12, 2016
an artist designs a mobile of light horizontal rods connected by vertical strings and supporting various shaped weights. Find the magnitudes w2, w3, and w4 if w1= 1.00 unit of weight. The numerical values given in the figure all have units of length.
May 2, 2016
What is the concentration of IO3- (total volume: 20mL) when you have .00001mol of HSO3- (total volume: 10mL)? Use the balanced equation IO3-(aq)+3HSO3-(aq)>>>I-(aq)+3SO4^2-(aq)+3H+(aq)
May 1, 2016
Science Check answers
2) What phenomenon naturally warms Earth's lower atmosphere and surface? the formation of sunspots changes in the shape of Earth's orbit global warming (MY ANSWER) the greenhouse effect 3) Which of the following is an example of human impact...
April 29, 2016
Use PV=nRT to find n, the moles of hydrogen gas. V= 1.68x10^-2 L P= 715 torr-VP of water at 25C (about 25 torr; look it up in Wikipedia) T= 298.2K R = Applicable value for the above units.
April 27, 2016
I'm having difficulty understanding density. I am trying to relate the concept of density to brownies. Should a brownie with baking soda have a higher or lower density compared to a brownie with no baking soda? Does a thick brownie mean a high or low density? When it says ...
April 24, 2016
A military gun is mounted on a railroad car (m = 1500 kg). There is no frictional force on the car, the track is horizontal, and the car is initially at rest. The gun then fires a shell of mass 30 kg with a velocity of 300 m/s at an angle of 40° with respect to the ...
April 23, 2016
two particles of mass m1=1.5 kg, and m2=3.5 kg undergo a 1-dimensional head-on collision. Their velocities along x are V1i=12 m/s, and V2i=-7.5 m/s. The 2 particles stick together after the collision. a.) Find the velocity after the collision. b.) How much kinetic energy is ...
April 23, 2016
A skier of mass 110 kg travels down a frictionless ski trial. a.) If the top of the trail is a height 200m above the bottom, what is the work done by gravity on the skier? b.) Find the velocity of the skier when he reaches the bottom of the ski trail. Assume he starts form ...
April 22, 2016
John can paint a room in 3 hours. His apprentice, working alone, requires 6 hours to do the same job. How long would it take John and his apprentice, working together, to paint the room if they continue to work at the given rates?
April 14, 2016
Squids and octopuses propel themselves by expelling water. They do this by taking the water into a cavity and then suddenly contracting the cavity, forcing the water to shoot out of an opening. A 6.50 daN squid (including the water in the cavity) that is at rest suddenly sees ...
April 11, 2016
A spring has an unstretched length of 10 cm . It exerts a restoring force F when stretched to a length of 12 cm . For what total stretched length of the spring is its restoring force 3F? At what compressed length is the restoring force 2F? I keep doing this but I do not think ...
April 11, 2016
Anna is designing rectangular garden that has an area of 182 square feet, and the length is longer than the width. The table lists the possible whole number dimensiones for the garden. Which dimensiones are missing?
April 4, 2016
A segment with endpoints (3, -2) and (4, 2) is dilated to the image segment with endpoints (9, -6) and (12, 6). What is the scale factor for the dilation? 3 2 6 **my choice 9 **i feel its this one too, im stuck
March 31, 2016
Why does the Rabbi's son abandon his father on the march to Buchenwald? He believes his father is better off without him. He wants to be free from the responsibility of his father. He doesn't want to tell his father he doesn't believe in God. <~my choice He ...
March 29, 2016
The length of a rectangular piece of steel in a bridge is 4 meters less than triple the width. The perimeter of the piece of steel is 56 meters. Find the length of the piece of steel. Find the width of the piece of steel.
March 22, 2016
two cruise ships sail from NY to FL.ONE ship make the round trip in 8 days.the other ship make the round trip in 10 days.both ships sail from ny today.which is the fewest number of days before both ships will sail again from newyork on the same day?
March 19, 2016
Aj bought a portable game system on sale for $150.the portable game system was 70% of the regular price.aj concluded that the original price of the portable game system must have been $225. Aj correct? justify your answers part b is 70% of an original price the same 30% of an ...
March 19, 2016
A rectangular lap pool has a constant depth. The length of the pool is 9 times the width, and the surface area of the water is 81 square feet. What are the dimensions of the pool? Include units.
March 17, 2016
magine you work in a steel mill in a large industrial city in England in the late 1800s. You live in a neighborhood with other factory workers, and share the same living and working conditions they do. Write a letter to your representative in Parliament expressing your ...
March 16, 2016
Women and overweight people often experience backpain. Let us explore the reason for this. Assume the women has a weight of 60.0 daN before pregnancy. Suppose she gains 10.0 daN during pregnancy, due to weight of the fetus, placenta, amniotic fluid, etc. To make the ...
March 15, 2016
A triangular pyramid is defined by the points .The pyramid is then reflected over the xz-plane. The reflected image is then translated 3 units back, 2 units left, and 4 units up. Write the general rule you use for the reflection. Show the results of your calculations for the ...
March 11, 2016
Toronto is playing Anaheim in the Stanley cup final. The first team to win four games is the new NHL champion. If the probability of that Toronto will win any game is 0.55 determine the probability that Anaheim wins the Stanley Cup.
March 7, 2016
You have 775 mL of an 0.11 M acetic acid solution. What volume (V) of 1.10 M NaOH solution must you add in order to prepare an acetate buffer of pH = 5.05? (The pKa of acetic acid is 4.76.) I don't know what to do!!! HELP!!!!
February 28, 2016
What does the radius of a sphere join? any two points on the sphere and does not contain the center any two points on the sphere and contains the center <~my choice any two points on the sphere the center and a point on the sphere
February 25, 2016
What does the diameter of a sphere join? any two points on the sphere any two points on the sphere and contains the center <~my choice any two points on the sphere and does not contain the center the center and a point on the sphere
February 24, 2016
THis is the question posed to me by mi bio teacher. THe more specific of it it is, "find the masss of a liver cell, assuming it has the shape of a cube, with the diameter and density of water."
February 23, 2016
What did John Locke believe? Absolute monarchs have the right to rule through divine right. God should not be involved in the affairs of mankind. All governments should have three branches with equal power. <~my choice It is the governments job to protect the natural rights...
February 19, 2016
2. In the space below, create a simple time line that traces the emergence of a constitutional monarchy in England during the seventeenth century. It is not necessary to include exact dates, but events should be in the correct order. Include at least eight events that were ...
February 12, 2016
1. Explain from the Gilded Age that supports the "the farmers were up in arms." 2. What is one change in the South between 1877 and 1900 that reflected the policies of the New South agenda?
February 4, 2016
I got it it was 2.1 x .5 then i calculated it now I am trying to figure out What the car's displacement is from its original position? how would I figure that out do I divide from the 2.1 and the 1.05?
January 31, 2016
A circular test track for cars has a circumference of 2.1 km . A car travels around the track from the southernmost point to the northernmost point what distance does the car travel?
January 31, 2016
A certain amount of calcium reacts with water and the formed hydroxide 49g completely neutralized phosphoric acid. Calculate the volume of hydrogen obtained, at STP, and the mass of calcium.
January 22, 2016