# a balloon filled with helium has a volume of 1.28

18,282 results

**Physics**

A clown at a birthday party has brought along a helium cylinder, with which he intends to fill balloons. When full, each balloon contains 0.036 m3 of helium at an absolute pressure of 1.2 x 10^5 Pa. The cylinder contains helium at an absolute pressure of 1.6 x 10^7 Pa and has ...

**Chemistry**

A hot air balloon is filled with hot air and the hot air forces the volume of the balloon to expand until the density of the gas in the balloon is less than the density of the outside air. The volume must be 20% larger than the balloon would be at STP in order for the balloon ...

**chemistry**

A hot air balloon is filled with hot air and the hot air forces the volume of the balloon to expand until the density of the gas in the balloon is less than the density of the outside air. The volume must be 20% larger than the balloon would be at STP in order for the balloon ...

**chemistry (charles law)**

1.)A ballon is filled with 3.0L of helium at 310k.The balloon is placed in an oven where the temputure reaches 340k.what is the new volume of the ballon?

**Chemistry**

Fill a balloon with helium gas to a volume of 2.68 L at 23 celsius and 789mmHg. What would the volume of helium if the pressure changes to 632 mmHg but the temperature is unchanged. This is how I solved it V2 = V1 X P1/P2 2.68L X 23/789 = V2 =.078 L Is this correct

**Physics**

I NEED HELP! Already answered on here but does not make sense/work. Please HELP! A 2.7 kg balloon is filled with helium ( density = 0.179 kg/m^3). If the balloon is a sphere with a radius of 5.2m , what is the maximum weight it can lift?

**Physics**

If a balloon is filled with helium gas of molar mass 4x10^-3, at a pressure of 1*10^5, What is the number of moles of gas in the balloon?

**Science HELP!**

If a balloon is filled with helium gas of molar mass 4x10^-3, at a pressure of 1*10^5, What is the number of moles of gas in the balloon?

**math**

Caitlyn bought a helium tank to fill spherical balloons for a party. If the diameter of the filled balloons are 14.4 inches, how much helium would be needed in each balloon?

**science**

hellium gas is added to a balloon already partially filled with helium gas.why does the balloon inflate?

**Physics**

Hey can someone help me out? I only have 1 attempt left on this question and do not understand it at all!!! A 3.5 kg balloon is filled with helium ( density = 0.179 kg/m^3). If the balloon is a sphere with a radius of 5.2m , what is the maximum weight it can lift?

**Physics**

To an order of magnitude, how many helium-filled toy balloons would be required to lift you? Because helium is an irreplaceable resource, develop a theoretical answer rather than an experimental answer. Assume that you have a mass of approximately 70 kg, the radius of a ...

**PHYSICS! HELIUM BALLON**

Under standard conditions, the density of air is 1.293 kg/m3 and that of helium is 0.178 kg/m3. A spherical helium balloon lifts a basket plus cargo of mass 277.0 kg. What must be the minimum diameter of the spherical balloon?

**Chemistry**

A balloon holds 27.8 kg of helium. What is the volume of the balloon if the pressure is 0.97 atm and the temperature is 24 °C

**physics**

The total mass of helium in a balloon is 114 kg. What is the volume of the balloon?

**physics**

The total mass of helium in a balloon is 114 kg. What is the volume of the balloon?

**chemistry**

A balloon is filled to a volume of 5.0 102 mL at a temperature of 28.0°C. The balloon is then cooled at constant pressure to a temperature of 1.00 102 K. What is the final volume of the balloon? the answer i got is v=166.66666667 My question is what is the correct sig. ...

**chemistry**

A helium-ﬁlled balloon has a volume of 2.83 L at 30 ◦ C. The volume of the balloon decreases to 2.35 L after it is placed outside on a cold day. What is the outside temperature in K? Answer in units of K?

**Chemistry**

Fill a balloon with helium gas to a volume of 2.68 L at 23 celsius and 789mmHg. What would the volume of helium if the pressure changes to 632 mmHg but the temperature is unchanged. This is how I solved it V2 = V1 X P1/P2 2.68L X 789/632 = ANSWER V2 =.3.35 L Is this correct

**physics**

A light spring with a spring constant of 105.0 N/m rests vertically on the table, as shown in (a) below. A 2.05 g balloon is filled with helium (0°C and 1 atm pressure) to a volume of 4.64 m3 and connected to the spring, causing the spring to stretch, as shown in (b) below. ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area of the balloon is 0.11 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.7 kg m-3. Under these conditions the total surface area of the balloon is 0.52 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.87 kg m-3. Under these conditions the total surface area of the balloon is 0.87 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.5 kg m-3. Under these conditions the total surface area of the balloon is 0.72 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.5 kg m-3. Under these conditions the total surface area of the balloon is 0.72 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area of the balloon is 0.11 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chimistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.82 kg m-3. Under these conditions the total surface area of the balloon is 0.39 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.87 kg m-3. Under these conditions the total surface area of the balloon is 0.87 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.79 kg m-3. Under these conditions the total surface area of the balloon is 0.47 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.86 kg m-3. Under these conditions the total surface area of the balloon is 0.56 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Problem**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.92 kg m-3. Under these conditions the total surface area of the balloon is 0.26 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.92 kg m-3. Under these conditions the total surface area of the balloon is 0.26 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.88 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Physics**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.88 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.66 kg m-3. Under these conditions the total surface area of the balloon is 0.88 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**science**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.23 kg m-3. Under these conditions the total surface area of the balloon is 0.46 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.3 kg m-3. Under these conditions the total surface area of the balloon is 0.33 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**physics**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.72 kg m-3. Under these conditions the total surface area of the balloon is 0.17 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**physics**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.72 kg m-3. Under these conditions the total surface area of the balloon is 0.17 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.3 kg m-3. Under these conditions the total surface area of the balloon is 0.33 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.55 kg m-3. Under these conditions the total surface area of the balloon is 0.78 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**CHEM**

How many grams of helium must be added to a balloon containing 8.00 g of helium gas to double its volume. Assume no temp or pressure change.

**Chemistry**

A helium balloon contains 0.54g of helium. Given the molecular weight of helium is 4.0 g/mol, how many moles of helium does it contain?

**chemistry**

A helium balloon contains 0.30g of helium. Given the molecular weight of helium is 4.0 g/mol, how many moles of helium does it contain?

**Chemistry**

A helium balloon contains 0.50 g of helium. Given the molecular weight of helium is 4.0 g/mol, how many moles of helium does it contain?

**Chemistry**

need to know how to solve the following.... a gas filled weather balloon floating in the atomsphere has an initial volume of 850 L. The balloon rises to a region where the pressure is 56 kPa and its volume expands to 1700 L. If the temperature remains the same, what was the ...

**Statistics**

Does a football filled with helium travel farther than one filled with ordinary air? To test this, the Columbus Dispatch conducted a study. Two identical footballs, one filled with helium and one filled with ordinary air, were used. A casual observer was unable to detect a ...

**CHEM**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.43 kg m-3. Under these conditions the total surface area of the balloon is 0.68 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**science**

Why does a helium-filled balloon float up when it is released?

**Chemistry**

The total mass that can be lifted by a balloon is given by the difference between the mass of air displaced by the balloon and the mass of the gas inside the balloon. Consider a hot air balloon that approximates a sphere 5.00 m in diameter and contains air heated to 65 C. The ...

**Chemistry**

The total mass that can be lifted by a balloon is given by the difference between the mass of air displaced by the balloon and the mass of the gas inside the balloon. Consider a hot air balloon that approximates a sphere 5.00 m in diameter and contains air heated to 65 C. The ...

**chemistry**

a 3.0L helium balloon is placed in a car sitting in hot sunlight. The temperature in the mall, when the balloon was bought, was 22C. The temperature in the car is 45C. what will be the new volume of the of the balloon. Will it be: 6.14L? I would think this looks right but the ...

**Chemistry**

A balloon is filled with 0.75 L of helium gas at 1 atm pressure and 25 degrees Celsius. The balloon is released and floats upward in the atmosphere. The temperature drops to 23 degrees Celsius and the balloon expands to 1.50 L. What is the pressure at this altitude? Assume the...

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.53 kg m-3. Under these conditions the total surface area of the balloon is 0.2 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry**

A balloon is filled to a volume of 1.0 102 mL at a temperature of 38.0°C. The balloon is then cooled at constant pressure to a temperature of 1.00 multiplied by 102 K. What is the final volume of the balloon?

**Chemistry**

A meteorological balloon contains 237. L of helium at 33. °C and 0.832 atm. If the volume of the balloon can vary according to external conditions, what volume would it occupy at an altitude at which the temperature is -57. °C and the pressure is 0.094 atm? (2 significant ...

**Chemistry**

A Helium Gas Ballon Has A Volume Of 12.0L. At Room Temperature(25 Degrees Celcius) The Internal Pressure Is .05ATM. Calculate The Number Of Moles Of Helium In The Balloon?

**chemistry**

calculate the density of helium in a helium balloon at 21.7 degress celsius. (Assume that the pressure inside the balloon is 1.15 atm.)

**osu**

a balloon is filled with .50 moles out of gas at room temp and normal room pressure, the balloon volume would be 11.2L. if you heat the balloon keeping the room pressure and amount of gas unchanging, what would be the effect on the volume of the balloon?

**Physics**

Helium balloons are used regularly in scientific research. A typical balloon would reach an altitude of 40.0 km with an air density of 4.3*10^-3 kg/m^3. At this altitude the helium in the balloon would expand to 540000.0m^3. Find the buoyant force on the balloon.

**math**

A spherical helium balloon has a diameter of 30 cm. How much helium is needed to fill the balloon, in cubic centimeters? Round your answer to the nearest centimeter

**AP Chemistry**

A balloon is filled to a volume of 2.0 102 mL at a temperature of 33.0°C. The balloon is then cooled at constant pressure to a temperature of 1.00 102 K. What is the final volume of the balloon?

**Physics**

A clown at a birthday party has brought along a helium cylinder, with which he intends to fill balloons. When full, each balloon contains 0.00280 m3 of helium at an absolute pressure of 1.20 x 105 Pa. The cylinder contains helium at an absolute pressure of 2.90 x 107 Pa and ...

**physics**

A WEATHER BALLOON IS TO OPERATE WHERE THE DENSITY OF AIR IS 0.9Kg/m3. THE BALLOON HAS A VOLUME OF 20cm3 AND IS FILLED WITH NITROGEN WITH DENSITY 0.09Kg/m3. IF THE BALLOON BAG WEIGHS 118N, WHAT LOAD CAN IT SUPPORT AT THIS ALTITUDE?

**Chemistry**

At 25 degree celsius, which balloon has the greater volume, an oxygen balloon O2 at 1.2 atm with a mass of 16.0 g, or helium He balloon at 1.2 atm with a mass of 2.0 g?

**Chemistry**

Calculate the mass of air in an air-filled tire and the mass of helium in a helium-filled tire. What is the mass difference between the two? Assume that the volume of the tire is 857 , that it is filled with a total pressure of 125 psi, and that the temperature is 26 . Also, ...

**chem**

A balloon holds 29.3 kg of helium. What is the volume of the balloon if the final pressure is 1.2 atm and the temperature is 22°C? using the equation pv=nrt would i put 29.3 kg in place of n? but n has to be in moles so how do you convert that? thanks

**Chemistry**

A large balloon contains 65.0 L of helium gas at 25 °C and a pressure of 745 mm Hg. The balloon ascends to 3000 m, at which the external pressure has decreased by 30.%. What would be the volume of the balloon, assuming it expands so that the internal and external pressures ...

**Chemistry**

A cylinder containing 15.0 L of helium gas at a pressure of 165 atm is to be used to fill party balloons. Each balloon must be filled to a volume of 2.0 L at a pressure of 1.1 atm. What is the maximum number of balloons that can be inflated? Assume that the gas in the cylinder...

**chemistry**

A balloon filled with 85 g of nitrogen gas that produced a pressure of 3.25 atm at 58C. What is the volume of the balloon/

**chemistry**

A balloon is filled with 2.2 cm3 helium gas at 132.4 atm pressure. What will be the new pressure (atm) if the volume is changed to 68.6 cm3?

**math**

A study to determine whether or not a football filled with helium traveled farther when kicked than one filled with air found that while the football filled with helium went, on average, farther than the one filled with air, the difference was not statistically significant. ...

**Physics**

A rigid tank having a volume of 0.100 m3 contains helium gas at 150 atm. How many balloons can be inflated by opening the valve at the top of the tank? Each filled balloon is a sphere 0.300 m in diameter at an absolute pressure of 1.30 atm.

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area of the balloon is 0.11 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**Chemistry (Check)**

What is the volume of the gas in a balloon at -195 degrees C if the balloon has been filled to a volume of 5.0L at 25 degrees C? Vf = 1.3L

**Chem**

A balloonist is preparing to make a trip in a helium-filled balloon. The trip begins in early morning at a temperature of 15 degrees C. By midafternoon, the temperature has increased to 30. degrees C. Assuming the pressure remains constant at 1.00atm, for each mole of helium, ...

**chem**

A balloon is filled with He to a pressure of 1.06 atm. The volume of the balloon at 25oC is 1.30 x 104 L. How many cylinders of He gas are needed to fill the balloon if the pressure in the cylinder at 20oC is 98.5 atm and the volume of the cylinder is 40.0 L. [You may have ...

**chemistry 106**

A gas-filled balloon having a volume of 1.50 L at 1.2 atm and 25°C is allowed to rise to the stratosphere (about 30 km above the surface of Earth), where the temperature and pressure are -23°C and 3.00 multiplied by 10-3 atm, respectively. Calculate the final volume of the ...

**Science**

When a balloon filled with any gas and the end is tied. It is left in the air. What changes occur in the volume of the balloon? Give reason.

**Chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.43 kg m-3. Under these conditions the total surface area of the balloon is 0.68 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

**PHYSICS**

A 30 kg. balloon is filled with 100 m to the third power of helium. how much force is needed to hold it down?

**physics**

The largest ballon ever flown had a volume of 53 million cubic feet. The thickness of the fabric is only 0.013mm. The balloon would reach an altitude of 150,000 ft. ( 46 km). The atmospheric pressure at that altitude is about 2*10^-3kg/m^3. The pressure of the helium was the ...

**Chem**

Can you please tell me if these are right? A gas has a volume of 2.8 L at a temperature of 27 degrees C. What temperature degrees C is needed to expand the volume to 15 L? (P and n are constant.) I got 1334 degress C Combined gas law problem a balloon is filled with 500.0 mL ...

**Chemistry**

A balloon is floating around outside your window. The temperature outside is 39 degree celsius, and the air pressure is 0.800atm . Your neighbor, who released the balloon, tells you that he filled it with 3.10 moles of gas. What is the volume of gas inside this balloon?

**Chemistry**

1. An empty balloon weighs 10.0 g and is filled to a volume of 20.0 L with CO gas. If the density of air at 25.0 °C and 1.00 atm is 1.17 g/L, will the balloon float? 2. Determine the volume of gas produced at 20.0 °C and 1.00 atm from the complete combustion of 1.0 kg of ...

**physics**

Two copper cylinders, immersed in a water tank at 46.3°C contain helium and nitrogen, respectively. The helium-filled cylinder has a volume twice as large as the nitrogen-filled cylinder. a) Calculate the average kinetic energy of a helium molecule at 46.3°C. b) Calculate ...

**physics**

Two copper cylinders, immersed in a water tank at 46.3°C contain helium and nitrogen, respectively. The helium-filled cylinder has a volume twice as large as the nitrogen-filled cylinder. a) Calculate the average kinetic energy of a helium molecule at 46.3°C. b) Calculate ...

**Physics**

Two copper cylinders, immersed in a water tank at 46.3°C contain helium and nitrogen, respectively. The helium-filled cylinder has a volume twice as large as the nitrogen-filled cylinder. a) Calculate the average kinetic energy of a helium molecule at 46.3°C. b) Calculate ...

**Chemistry**

A gas-filled balloon having a volume of 3.50 L at 1.2 atm and 25°C is allowed to rise to the stratosphere (about 30 km above the surface of Earth), where the temperature and pressure are −23°C and 3.00 10−3 atm, respectively. Calculate the final volume of the ...

**classical mechanics**

Buoyant Force of a Balloon (9 points possible) Helium balloons are used regularly in scientific research. A typical balloon would reach an altitude of 35.0 km with an air density of kg/m . At this altitude the helium in the balloon would expand to 540000.0 m . Find the buoyant...

**Chemistry**

A Balloon Time® tank holds 15% excess capacity to fill 50 helium balloons measuring 9” or 0.5 ft3 in volume at 1 atm and 22 oC. The gauge pressure of a new tank is 260 psi. What is the volume of a Balloon Time® tank in ft3?

**chemistry**

A helium balloon contains 0.26 g of helium. How many moles of helium does it contain?

**Math**

A balloon filled with helium is released from a height of 6 feet. The balloon rises at a constant rate of 3 feet per second. Which equation represents the height of the balloon (y), x seconds after it was released. y = 3x + 6 y = 6x + 3 x = 3y + 6 x = 6y + 3 <--? Using your...

**Science- physics**

A balloon weighing 80 kg has a capacity of 1200 m3. If it is filled with helium, how great a payload can it support? The density of helium is 0.18 kg/m3 and the density of air is 1.30 kg/m3. Express your answer in Newtons. I know the answer is 12, 400 Newtons I just don't know...

**Physics**

A balloon has a volume of 1000 m3 and a mass of 500 kg when empty. When full of helium, what is the maximum mass it can lift off the ground? The density of helium is 0.18 kg/m3 and the density of air is 1.29kg/m3.

**chemistry**

a balloonist is preparing a trip in a helium balloon. the trip begins in early morning at a temp of 15 degrees Celcius. By mid afternoon, the temp has increased to 30 degrees C. assuming the pressure remains constant at 1.00 atm, for each mole of helium, calculate: 1. the ...