Tommy

Em muốn hỏi là gia đình em có công Ty o việtnam và muốn cho anh chị em cua em o bên mỹ tiền theo cách hợp pháp, để mỹ Ko thể bắt bẻ được tại sao Lại có nhiều tiền mat. Vay trong trường hợp nay em phải viết thư như thế nào, và có thư mẫu ko a. Em cam on

1. The paintings discovered by Maria, daughter of Marcelino Sanzde Sautoula were paintings of an extinct type of _________________.

2.How many years ago did humans start creating images?

A. 3500 years ago

B. 350 years ago

C. 35,00 years ago

3.According to the documentary, what was the Prehistoric painter's obsession?

A. Landscaped

B. Animals

C. Humans

4.What did Henri Breuil believe the cave paintings depicted?

A. Hunting

B. Religious Ceremonies

C. Art for art sake

5.Where are Prehistoric cave paintings usually located within the cave?

A. Deep in the caves

B. On the exterior of the caves

C. At the entrance of the caves

6.Are Prehistoric cave paintings always representational?

A. No

B. Yes

7.Why did the man who had never seen an image before say he could not recognize the picture as a horse?

A. He could not walk around the horse.

B. He was blind.

C. He had never seen a horse before.

8.What was it about the paintings that led Dr. Williams to theorize that these figures were in the spirit world?

A. The large number of gods shown in the paintings.

B. The lack of any figural imagery in the paintings.

C. The paintings of figures that were made up of both human and animal characteristics.

9.When did humans stop painting on cave walls?

A. 1,000 years ago

B. 20,000 years ago

C.10,000 years ago

What is the pH of the buffer after adding 0.020 mol solid NaOH?

The blades of a fan rotate at a rate of 25 revolutions per second. When the fan is turned off, the blades come to rest in 8.0 s with constant angular acceleration.

a.What is the angular acceleration of the blades?

b.Through what angular displacement do the blades turn while coming to rest?

4.Ball A has a mass of 2.0 kg and moves with a velocity of 2.0 m/s at an angle of 30o relative to the positive x-axis. Ball B has a mass of 3.0 kg and moves with a velocity of 4.0 m/s at an angle of 40o relative to the positive y-axis. Determine the total momentum vector of the two balls.

5.The blades of a fan rotate at a rate of 25 revolutions per second. When the fan is turned off, the blades come to rest in 8.0 s with constant angular acceleration.

a.What is the angular acceleration of the blades?

b.Through what angular displacement do the blades turn while coming to rest?

1.A person pushes horizontally with a force of 350 N on a 50 kg crate to move it across a level floor. The coefficient of kinetic friction between the crate and the floor is 0.50. Find the magnitude of the frictional force and the acceleration of the crate.

2.A block of mass 2.0 kg is pushed down on a vertically oriented spring that has a spring constant of 1500N/m.. Initially, the spring is compressed by 5.0 cm and the block is at rest. When the block is released, it accelerates upward. Find the speed of the block when the spring has returned to its equilibrium position.

3.The collision between a hammer and a nail can be considered to be approximately elastic. Assume that the nail, initially at rest, is struck by a 500-g hammer moving with an initial speed of 5.0 m/s. If the speed of the hammer is 4.6 m/s after the collision, calculate the following:

a.Kinetic energy of the nail after the collision

b.Momentum of the nail after the collision

c.The mass of the nail.

4.A vertical spring stretches 20 cm when a 5.0 kg block is hung from its end. Calculate the spring constant. This block is then displaced an additional 10 cm downward and released. Find the period, frequency, and amplitude of the block's motion.

5.A certain guitar string of length 1.0 m has a mass of 7.0 g. When properly tuned, the string has a third harmonic of 770 Hz. What is the tension for properly tuning this string?

6.A solid hoop (I = MR2) starts from rest at the top of a ramp that is 3.0 m long and is inclined at an angle of 300 relative to the horizontal. The mass of the solid hoop is 12 kg and its radius is 10 cm. What is the linear velocity of the hoop when it reaches the bottom of the ramp?

A. cerebrum

B. cerebellum

C. hypothalamus

Mass of empty flask is 25.567

Mass of flask with 2 propanol is 33.751

Mass of 2 propanol is 8. 184

Volume 2 propanol ?

Density 3 propanol ?

1. dy/dx if y = 2x^3

2. dy/dx if y = x-1/x

3. dy/dx if y = square root of 2x+1?

Complete combustion of 3.40 g of a hydrocarbon produced 10.9 g of CO2 and 3.73 g of H2O. What is the empirical formula for the hydrocarbon?

CH

An unknown compound contains only C, H, and O. Combustion of 3.60 g of this compound produced 7.19 g of CO2 and 2.94 g of H2O.

CHO